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Von Neumann architecture
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See also: Stored-program computer and Universal Turing machine § Stored-program computer
Von Neumann architecture scheme
The von Neumann architecture—also known as the von Neumann model or Princeton architecture—is a computer architecture based on a 1945 description by the mathematician and physicist John von Neumann and others in the First Draft of a Report on the EDVAC.[1] That document describes a design architecture for an electronic digital computer with
A processing unit that contains an arithmetic logic unit and processor registers
A control unit that contains an instruction register and program counter
Memory that stores data and instructions
External mass storage
Input and output mechanisms[1][2]
The word has evolved to mean any stored-program computer in which an instruction fetch and a data operation cannot occur at the same time because they share a common bus. This is referred to as the von Neumann bottleneck and often limits the performance of the system.[3]
The design of a von Neumann architecture machine is simpler than a Harvard architecture machine—which is also a stored-program system but has one dedicated set of address and data buses for reading and writing to memory, and another set of address and data buses to fetch instructions.
A stored-program digital computer keeps both program instructions and data in read-write, random-access memory (RAM). Stored-program computers were an advancement over the program-controlled computers of the 1940s, such as the Colossus and the ENIAC. Those were programmed by setting switches and inserting patch cables to route data and control signals between various functional units. The vast majority of modern computers use the same memory for both data and program instructions. The von Neumann vs. Harvard distinction applies to the cache architecture, not the main memory (split cache architecture).
Contents
1 History
2 Capabilities
3 Development of the stored-program concept
4 Early von Neumann-architecture computers
5 Early stored-program computers
6 Evolution
7 Design limitations
7.1 Von Neumann bottleneck
7.1.1 Mitigations
7.2 Self-modifying code
8 See also
9 References
10 Further reading
11 External links
History[edit]
The earliest computing machines had fixed programs. Some very simple computers still use this design, either for simplicity or training purposes. For example, a desk calculator (in principle) is a fixed program computer. It can do basic mathematics, but it cannot run a word processor or games. Changing the program of a fixed-program machine requires rewiring, restructuring, or redesigning the machine. The earliest computers were not so much "programmed" as "designed" for a particular task. "Reprogramming"—when possible at all—was a laborious process that started with flowcharts and paper notes, followed by detailed engineering designs, and then the often-arduous process of physically rewiring and rebuilding the machine. It could take three weeks to set up and debug a program on ENIAC.[4]
With the proposal of the stored-program computer, this changed. A stored-program computer includes, by design, an instruction set, and can store in memory a set of instructions (a program) that details the computation.
A stored-program design also allows for self-modifying code. One early motivation for such a facility was the need for a program to increment or otherwise modify the address portion of instructions, which operators had to do manually in early designs. This became less important when index registers and indirect addressing became usual features of machine architecture. Another use was to embed frequently used data in the instruction stream using immediate addressing. Self-modifying code has largely fallen out of favor, since it is usually hard to understand and debug, as well as being inefficient under modern processor pipelining and caching schemes.
Capabilities[edit]
On a large scale, the ability to treat instructions as data is what makes assemblers, compilers, linkers, loaders, and other automated programming tools possible. It makes "programs that write programs" possible.[5] This has made a sophisticated self-hosting computing ecosystem flourish around von Neumann architecture machines.
Some high level languages such as LISP leverage the von Neumann architecture by providing an abstract, machine-independent way to manipulate executable code at runtime, or by using runtime information to tune just-in-time compilation (e.g. in the case of languages hosted on the Java virtual machine, or languages embedded in web browsers).
On a smaller scale, some repetitive operations such as BITBLT or pixel and vertex shaders can be accelerated on general purpose processors with just-in-time compilation techniques. This is one use of self-modifying code that has remained popular.
Development of the stored-program concept[edit]
The mathematician Alan Turing, who had been alerted to a problem of mathematical logic by the lectures of Max Newman at the University of Cambridge, wrote a paper in 1936 entitled On Computable Numbers, with an Application to the Entscheidungsproblem, which was published in the Proceedings of the London Mathematical Society.[6] In it he described a hypothetical machine he called a universal computing machine, now known as the "Universal Turing machine". The hypothetical machine had an infinite store (memory in today's terminology) that contained both instructions and data. John von Neumann became acquainted with Turing while he was a visiting professor at Cambridge in 1935, and also during Turing's PhD year at the Institute for Advanced Study in Princeton, New Jersey during 1936 – 1937. Whether he knew of Turing's paper of 1936 at that time is not clear.
In 1936, Konrad Zuse also anticipated in two patent applications that machine instructions could be stored in the same storage used for data.[7]
Independently, J. Presper Eckert and John Mauchly, who were developing the ENIAC at the Moore School of Electrical Engineering, at the University of Pennsylvania, wrote about the stored-program concept in December 1943. [8][9] In planning a new machine, EDVAC, Eckert wrote in January 1944 that they would store data and programs in a new addressable memory device, a mercury metal delay line memory. This was the first time the construction of a practical stored-program machine was proposed. At that time, he and Mauchly were not aware of Turing's work.
Von Neumann was involved in the Manhattan Project at the Los Alamos National Laboratory, which required huge amounts of calculation. This drew him to the ENIAC project, during the summer of 1944. There he joined into the ongoing discussions on the design of this stored-program computer, the EDVAC. As part of that group, he wrote up a description titled First Draft of a Report on the EDVAC[1] based on the work of Eckert and Mauchly. It was unfinished when his colleague Herman Goldstine circulated it with only von Neumann's name on it, to the consternation of Eckert and Mauchly.[10] The paper was read by dozens of von Neumann's colleagues in America and Europe, and influenced the next round of computer designs.
Jack Copeland considers that it is "historically inappropriate, to refer to electronic stored-program digital computers as 'von Neumann machines'".[11] His Los Alamos colleague Stan Frankel said of von Neumann's regard for Turing's ideas:
I know that in or about 1943 or '44 von Neumann was well aware of the fundamental importance of Turing's paper of 1936… Von Neumann introduced me to that paper and at his urging I studied it with care. Many people have acclaimed von Neumann as the "father of the computer" (in a modern sense of the term) but I am sure that he would never have made that mistake himself. He might well be called the midwife, perhaps, but he firmly emphasized to me, and to others I am sure, that the fundamental conception is owing to Turing— in so far as not anticipated by Babbage… Both Turing and von Neumann, of course, also made substantial contributions to the "reduction to practice" of these concepts but I would not regard these as comparable in importance with the introduction and explication of the concept of a computer able to store in its memory its program of activities and of modifying that program in the course of these activities. [12]
At the time that the "First Draft" report was circulated, Turing was producing a report entitled Proposed Electronic Calculator. It described in engineering and programming detail, his idea of a machine he called the Automatic Computing Engine (ACE).[13] He presented this to the Executive Committee of the British National Physical Laboratory on February 19, 1946. Although Turing knew from his wartime experience at Bletchley Park that what he proposed was feasible, the secrecy surrounding Colossus, that was subsequently maintained for several decades, prevented him from saying so. Various successful implementations of the ACE design were produced.
Both von Neumann's and Turing's papers described stored-program computers, but von Neumann's earlier paper achieved greater circulation and the computer architecture it outlined became known as the "von Neumann architecture". In the 1953 publication Faster than Thought: A Symposium on Digital Computing Machines (edited by B. V. Bowden), a section in the chapter on Computers in America reads as follows:[14]
The Machine of the Institute For Advanced Studies, Princeton
In 1945, Professor J. von Neumann, who was then working at the Moore School of Engineering in Philadelphia, where the E.N.I.A.C. had been built, issued on behalf of a group of his co-workers, a report on the logical design of digital computers. The report contained a detailed proposal for the design of the machine that has since become known as the E.D.V.A.C. (electronic discrete variable automatic computer). This machine has only recently been completed in America, but the von Neumann report inspired the construction of the E.D.S.A.C. (electronic delay-storage automatic calculator) in Cambridge (see page 130).
In 1947, Burks, Goldstine and von Neumann published another report that outlined the design of another type of machine (a parallel machine this time) that would be exceedingly fast, capable perhaps of 20,000 operations per second. They pointed out that the outstanding problem in constructing such a machine was the development of suitable memory with instantaneously accessible contents. At first they suggested using a special vacuum tube—called the "Selectron"—which the Princeton Laboratories of RCA had invented. These tubes were expensive and difficult to make, so von Neumann subsequently decided to build a machine based on the Williams memory. This machine—completed in June, 1952 in Princeton—has become popularly known as the Maniac. The design of this machine inspired at least half a dozen machines now being built in America, all known affectionately as "Johniacs."
In the same book, the first two paragraphs of a chapter on ACE read as follows:[15]
Automatic Computation at the National Physical Laboratory
One of the most modern digital computers which embodies developments and improvements in the technique of automatic electronic computing was recently demonstrated at the National Physical Laboratory, Teddington, where it has been designed and built by a small team of mathematicians and electronics research engineers on the staff of the Laboratory, assisted by a number of production engineers from the English Electric Company, Limited. The equipment so far erected at the Laboratory is only the pilot model of a much larger installation which will be known as the Automatic Computing Engine, but although comparatively small in bulk and containing only about 800 thermionic valves, as can be judged from Plates XII, XIII and XIV, it is an extremely rapid and versatile calculating machine.
The basic concepts and abstract principles of computation by a machine were formulated by Dr. A. M. Turing, F.R.S., in a paper1. read before the London Mathematical Society in 1936, but work on such machines in Britain was delayed by the war. In 1945, however, an examination of the problems was made at the National Physical Laboratory by Mr. J. R. Womersley, then superintendent of the Mathematics Division of the Laboratory. He was joined by Dr. Turing and a small staff of specialists, and, by 1947, the preliminary planning was sufficiently advanced to warrant the establishment of the special group already mentioned. In April, 1948, the latter became the Electronics Section of the Laboratory, under the charge of Mr. F. M. Colebrook.
Early von Neumann-architecture computers[edit]
The First Draft described a design that was used by many universities and corporations to construct their computers.[16] Among these various computers, only ILLIAC and ORDVAC had compatible instruction sets.
ARC2 (Birkbeck, University of London) officially came online on May 12, 1948.[17]
Manchester Baby (Victoria University of Manchester, England) made its first successful run of a stored program on June 21, 1948.
EDSAC (University of Cambridge, England) was the first practical stored-program electronic computer (May 1949)
Manchester Mark 1 (University of Manchester, England) Developed from the Baby (June 1949)
CSIRAC (Council for Scientific and Industrial Research) Australia (November 1949)
EDVAC (Ballistic Research Laboratory, Computing Laboratory at Aberdeen Proving Ground 1951)
ORDVAC (U-Illinois) at Aberdeen Proving Ground, Maryland (completed November 1951)[18]
IAS machine at Princeton University (January 1952)
MANIAC I at Los Alamos Scientific Laboratory (March 1952)
ILLIAC at the University of Illinois, (September 1952)
BESM-1 in Moscow (1952)
AVIDAC at Argonne National Laboratory (1953)
ORACLE at Oak Ridge National Laboratory (June 1953)
BESK in Stockholm (1953)
JOHNNIAC at RAND Corporation (January 1954)
DASK in Denmark (1955)
WEIZAC at the Weizmann Institute of Science in Rehovot, Israel (1955)
PERM in Munich (1956?)
SILLIAC in Sydney (1956)
Early stored-program computers[edit]
The date information in the following chronology is difficult to put into proper order. Some dates are for first running a test program, some dates are the first time the computer was demonstrated or completed, and some dates are for the first delivery or installation.
The IBM SSEC had the ability to treat instructions as data, and was publicly demonstrated on January 27, 1948. This ability was claimed in a US patent.[19][20] However it was partially electromechanical, not fully electronic. In practice, instructions were read from paper tape due to its limited memory.[21]
The ARC2 developed by Andrew Booth and Kathleen Booth at Birkbeck, University of London officially came online on May 12, 1948.[17] It featured the first rotating drum storage device.[22][23]
The Manchester Baby was the first fully electronic computer to run a stored program. It ran a factoring program for 52 minutes on June 21, 1948, after running a simple division program and a program to show that two numbers were relatively prime.
The ENIAC was modified to run as a primitive read-only stored-program computer (using the Function Tables for program ROM) and was demonstrated as such on September 16, 1948, running a program by Adele Goldstine for von Neumann.
The BINAC ran some test programs in February, March, and April 1949, although was not completed until September 1949.
The Manchester Mark 1 developed from the Baby project. An intermediate version of the Mark 1 was available to run programs in April 1949, but was not completed until October 1949.
The EDSAC ran its first program on May 6, 1949.
The EDVAC was delivered in August 1949, but it had problems that kept it from being put into regular operation until 1951.
The CSIR Mk I ran its first program in November 1949.
The SEAC was demonstrated in April 1950.
The Pilot ACE ran its first program on May 10, 1950 and was demonstrated in December 1950.
The SWAC was completed in July 1950.
The Whirlwind was completed in December 1950 and was in actual use in April 1951.
The first ERA Atlas (later the commercial ERA 1101/UNIVAC 1101) was installed in December 1950.
Evolution[edit]
Single system bus evolution of the architecture
Through the decades of the 1960s and 1970s computers generally became both smaller and faster, which led to evolutions in their architecture. For example, memory-mapped I/O lets input and output devices be treated the same as memory.[24] A single system bus could be used to provide a modular system with lower cost[clarification needed]. This is sometimes called a "streamlining" of the architecture.[25] In subsequent decades, simple microcontrollers would sometimes omit features of the model to lower cost and size. Larger computers added features for higher performance.
Design limitations[edit]
Von Neumann bottleneck[edit]
The shared bus between the program memory and data memory leads to the von Neumann bottleneck, the limited throughput (data transfer rate) between the central processing unit (CPU) and memory compared to the amount of memory. Because the single bus can only access one of the two classes of memory at a time, throughput is lower than the rate at which the CPU can work. This seriously limits the effective processing speed when the CPU is required to perform minimal processing on large amounts of data. The CPU is continually forced to wait for needed data to move to or from memory. Since CPU speed and memory size have increased much faster than the throughput between them, the bottleneck has become more of a problem, a problem whose severity increases with every new generation of CPU.
The von Neumann bottleneck was described by John Backus in his 1977 ACM Turing Award lecture. According to Backus:
Surely there must be a less primitive way of making big changes in the store than by pushing vast numbers of words back and forth through the von Neumann bottleneck. Not only is this tube a literal bottleneck for the data traffic of a problem, but, more importantly, it is an intellectual bottleneck that has kept us tied to word-at-a-time thinking instead of encouraging us to think in terms of the larger conceptual units of the task at hand. Thus programming is basically planning and detailing the enormous traffic of words through the von Neumann bottleneck, and much of that traffic concerns not significant data itself, but where to find it.[26][27]
Mitigations[edit]
There are several known methods for mitigating the Von Neumann performance bottleneck. For example, the following all can improve performance[why?]:
Providing a cache between the CPU and the main memory
providing separate caches or separate access paths for data and instructions (the so-called Modified Harvard architecture)
using branch predictor algorithms and logic
providing a limited CPU stack or other on-chip scratchpad memory to reduce memory access
The problem can also be sidestepped somewhat by using parallel computing, using for example the non-uniform memory access (NUMA) architecture—this approach is commonly employed by supercomputers. It is less clear whether the intellectual bottleneck that Backus criticized has changed much since 1977. Backus's proposed solution has not had a major influence.[citation needed] Modern functional programming and object-oriented programming are much less geared towards "pushing vast numbers of words back and forth" than earlier languages like FORTRAN were, but internally, that is still what computers spend much of their time doing, even highly parallel supercomputers.
As of 1996, a database benchmark study found that three out of four CPU cycles were spent waiting for memory. Researchers expect that increasing the number of simultaneous instruction streams with multithreading or single-chip multiprocessing will make this bottleneck even worse.[28]
Self-modifying code[edit]
Aside from the von Neumann bottleneck, program modifications can be quite harmful, either by accident or design. In some simple stored-program computer designs, a malfunctioning program can damage itself, other programs, or the operating system, possibly leading to a computer crash. Memory protection and other forms of access control can usually protect against both accidental and malicious program modification.
See also[edit]
Computer science portal
CARDboard Illustrative Aid to Computation
Interconnect bottleneck
Little man computer
Random-access machine
Turing machine
Neuromorphic engineering
Eckert architecture
References[edit]
^ Jump up to: a b c von Neumann, John (1945), First Draft of a Report on the EDVAC (PDF), archived from the original (PDF) on 2013-03-14, retrieved 2011-08-24
Jump up ^ Ganesan 2009
Jump up ^ Markgraf, Joey D. (2007), The Von Neumann Bottleneck, archived from the original on December 12, 2013
Jump up ^ Copeland 2006, p. 104
Jump up ^ MFTL (My Favorite Toy Language) entry Jargon File 4.4.7, retrieved 2008-07-11
Jump up ^ Turing, Alan M. (1936), "On Computable Numbers, with an Application to the Entscheidungsproblem", Proceedings of the London Mathematical Society, 2 (published 1937), 42, pp. 230–265, doi:10.1112/plms/s2-42.1.230 (and Turing, Alan M. (1938), "On Computable Numbers, with an Application to the Entscheidungsproblem. A correction", Proceedings of the London Mathematical Society, 2 (published 1937), 43 (6), pp. 544–546, doi:10.1112/plms/s2-43.6.544 )
Jump up ^ "Electronic Digital Computers", Nature, 162: 487, September 25, 1948, doi:10.1038/162487a0, archived from the original on April 6, 2009, retrieved April 10, 2009
Jump up ^ Lukoff, Herman (1979). From Dits to Bits: A personal history of the electronic computer. Portland, Oregon, USA: Robotics Press. ISBN 0-89661-002-0. LCCN 79-90567.
Jump up ^ ENIAC project administrator Grist Brainerd's December 1943 progress report for the first period of the ENIAC's development implicitly proposed the stored program concept (while simultaneously rejecting its implementation in the ENIAC) by stating that "in order to have the simplest project and not to complicate matters," the ENIAC would be constructed without any "automatic regulation.".
Jump up ^ Copeland 2006, p. 113
Jump up ^ Copeland, Jack (2000), A Brief History of Computing: ENIAC and EDVAC, retrieved 2010-01-27
Jump up ^ Copeland, Jack (2000), A Brief History of Computing: ENIAC and EDVAC, retrieved 2010-01-27 which cites Randell, Brian (1972), Meltzer, B.; Michie, D., eds., "On Alan Turing and the Origins of Digital Computers", Machine Intelligence, Edinburgh: Edinburgh University Press, 7: 10, ISBN 0-902383-26-4
Jump up ^ Copeland 2006, pp. 108–111
Jump up ^ Bowden 1953, pp. 176,177
Jump up ^ Bowden 1953, p. 135
Jump up ^ "Electronic Computer Project". Institute for Advanced Study. Retrieved 2011-05-26.
^ Jump up to: a b Campbell-Kelly, Martin (April 1982). "The Development of Computer Programming in Britain (1945 to 1955)". IEEE Annals of the History of Computing. 4 (2): 121–139. doi:10.1109/MAHC.1982.10016.
Jump up ^ Robertson, James E. (1955), Illiac Design Techniques, report number UIUCDCS-R-1955-146, Digital Computer Laboratory, University of Illinois at Urbana-Champaign
Jump up ^ Selective Sequence Electronic Calculator (USPTO Web site)
Jump up ^ Selective Sequence Electronic Calculator (Google Patents)
Jump up ^ Grosch, Herbert R. J. (1991), Computer: Bit Slices From a Life, Third Millennium Books, ISBN 0-88733-085-1
Jump up ^ Lavington, Simon, ed. (2012). Alan Turing and his Contemporaries: Building the World's First Computers. London: British Computer Society. p. 61. ISBN 9781906124908.
Jump up ^ Johnson, Roger (April 2008). "School of Computer Science & Information Systems: A Short History" (PDF). Birkbeck College. University of London. Retrieved 2017-07-23.
Jump up ^ Bell, C. Gordon; Cady, R.; McFarland, H.; O'Laughlin, J.; Noonan, R.; Wulf, W. (1970), "A New Architecture for Mini-Computers—The DEC PDP-11" (PDF), Spring Joint Computer Conference, pp. 657–675
Jump up ^ Null, Linda; Lobur, Julia (2010), The essentials of computer organization and architecture (3rd ed.), Jones & Bartlett Learning, pp. 36, 199–203, ISBN 978-1-4496-0006-8
Jump up ^ Backus, John W. "Can Programming Be Liberated from the von Neumann Style? A Functional Style and Its Algebra of Programs". doi:10.1145/359576.359579.
Jump up ^ Dijkstra, Edsger W. "E. W. Dijkstra Archive: A review of the 1977 Turing Award Lecture". Retrieved 2008-07-11.
Jump up ^ Sites, Richard L.; Patt, Yale. "Architects Look to Processors of Future". Microprocessor report. 1996
Further reading[edit]
Bowden, B. V., ed. (1953), Faster Than Thought: A Symposium on Digital Computing Machines, London: Sir Isaac Pitman and Sons Ltd.
Rojas, Raúl; Hashagen, Ulf, eds. (2000), The First Computers: History and Architectures, MIT Press, ISBN 0-262-18197-5
Davis, Martin (2000), The universal computer: the road from Leibniz to Turing, New York: W. W. Norton & Company Inc., ISBN 0-393-04785-7 republished as: Davis, Martin (2001), Engines of Logic: Mathematicians and the Origin of the Computer, New York: W. W. Norton & Company, ISBN 978-0-393-32229-3
Can Programming be Liberated from the von Neumann Style?. Backus, John. 1977 ACM Turing Award Lecture. Communications of the ACM, August 1978, Volume 21, Number 8 Online PDF see details at http://www.cs.tufts.edu/~nr/backus-lecture.html
Bell, C. Gordon; Newell, Allen (1971), Computer Structures: Readings and Examples, McGraw-Hill Book Company, New York. Massive (668 pages)
Copeland, Jack (2006), "Colossus and the Rise of the Modern Computer", in Copeland, B. Jack, Colossus: The Secrets of Bletchley Park's Codebreaking Computers, Oxford: Oxford University Press, ISBN 978-0-19-284055-4
Ganesan, Deepak (2009), The von Neumann Model (PDF), retrieved 2011-10-22
McCartney, Scott (1999). ENIAC: The Triumphs and Tragedies of the World's First Computer. Walker & Co. ISBN 0-8027-1348-3.
Goldstine, Herman H. (1972). The Computer from Pascal to von Neumann. Princeton University Press. ISBN 0-691-08104-2.
Shurkin, Joel (1984). Engines of the Mind: A history of the Computer. New York, London: W. W. Norton & Company. ISBN 0-393-01804-0.
External links[edit]
Wikimedia Commons has media related to Von Neumann architecture.
Harvard vs von Neumann
A tool that emulates the behavior of a von Neumann machine[permanent dead link]
JOHNNY: A simple Open Source simulator of a von Neumann machine for educational purposes
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Hysterical strength
From Wikipedia, the free encyclopedia
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Hysterical strength is a display of extreme strength by humans, beyond what is believed to be normal, usually occurring when people are in life-and-death situations. Common anecdotal examples include parents lifting vehicles to rescue their children. The extra strength is commonly attributed to increased adrenaline production, though supporting evidence is scarce, and inconclusive when available; research into the phenomenon is difficult, though it is thought that it is theoretically possible.[1]
Extreme strength may occur during excited delirium.[2][3]
Contents
[hide]
1 Examples
2 Research
3 See also
4 References
Examples[edit]
The most common anecdotal examples are of parents lifting vehicles to rescue their children, and when people are in life-and-death situations. Hysterical strength can result in torn muscles due to higher mechanical stress.
In 1982, in Lawrenceville, Georgia, Tony Cavallo was repairing a 1964 Chevrolet Impala automobile from underneath. The vehicle was propped up with jacks, but it fell. Cavallo's mother, Mrs. Angela Cavallo, lifted the car high enough and long enough for two neighbours to replace the jacks and pull Tony from beneath the car.[4]
In 2006, Ivujivik, Quebec resident Lydia Angiyou saved several children by fighting a polar bear until a local hunter shot it.[5]
In 2006, in Tucson, Arizona, Tom Boyle watched as a Chevrolet Camaro hit 18-year-old Kyle Holtrust. The car pinned Holtrust, still alive, underneath. Boyle lifted the Camaro off the teenager, while the driver of the car pulled the teen to safety.[4][6]
In 2009, in Ottawa, Kansas, 1.70 m (5 ft 7 in), 84 kg (185 lb) Nick Harris lifted a Mercury sedan to help a 6-year-old girl pinned beneath.[7]
In 2011, in Tampa, Florida, 1.91 m (6 ft 3 in), 134 kg (295 lb) University of South Florida college football player Danous Estenor lifted a 1,600 kg (3,500 lb) car off of a man who had been caught underneath. The man was a tow truck driver who had been pinned under the rear tire of a 1990 Cadillac Seville, which had lurched forward as he worked underneath it. The man suffered only minor injuries.[8]
In 2012, in Glen Allen, Virginia, 22-year-old Lauren Kornacki rescued her father, Alec Kornacki, after the jack used to prop up his BMW slipped, pinning him under it. Lauren lifted the car, then performed CPR on her father and saved his life.[9]
In 2013, in Oregon, teenage sisters Hanna (age 16) & Haylee (age 14) lifted a tractor to save their father pinned underneath.[10]
In 2015, in St. John's, Newfoundland, Nick Williams lifted a four-wheel-drive vehicle to save a young boy pinned beneath its tire.[11]
In 2015, in Vienna, Virginia, Charlotte Heffelmire was able to momentarily use incredible strength to free her father from a GMC pick-up truck.[12]
Research[edit]
Early experiments showed that adrenaline increases twitch, but not tetanic force and rate of force development in muscles.[13] It is questionable, however, as to whether adrenaline, released from the adrenal medulla into the venous circulation, can reach the muscle quickly enough in order to be able to cause such an effect in the midst of a crisis. It may be that noradrenaline released from sympathetic nerve terminals directly innervating skeletal muscle,[14] has more of an effect over the timescale of seconds.
Amphetamine and other stimulants are used by some athletes for their psychological and performance-enhancing effects.[15][16] In competitive sports, this form of use is prohibited by anti-doping regulations.[15] In healthy people at oral therapeutic doses, amphetamine has been shown to increase physical strength,[15][17] acceleration,[15][17] stamina,[15][18] and endurance,[15][18] while reducing reaction time.[15] Like methylphenidate and bupropion, amphetamine increases stamina and endurance in humans primarily through reuptake inhibition and release of dopamine in the central nervous system.[17][18]
See also[edit]
Berserker
Double-muscle mutation in humans
Myostatin-related muscle hypertrophy
Muscle hypertrophy
Superhuman strength, similar concept in comic books and other fictional characters
References[edit]
Jump up ^ Ransom Riggs (25 March 2011). "Does Hysterical Strength Really Exist?". mentalfloss.com.
Jump up ^ "White Paper Report on Excited Delirium Syndrome" Archived October 11, 2010, at the Wayback Machine., ACEP Excited Delirium Task Force, American College of Emergency Physicians, September 10, 2009
Jump up ^ Sztajnkrycer, Matt D.; Baez, Amado A. "Cocaine, Excited Delirium and Sudden Unexpected Death" (PDF). Retrieved 29 November 2012.
^ Jump up to: a b Clark, Josh. "How can adrenaline help you lift a 3,500-pound car?", 11 December 2007. HowStuffWorks.com. Retrieved 13 November 2008.
Jump up ^ Jane George (2006-02-17). "Polar bear no match for fearsome mother in Ivujivik". Nunatsiaq News / Nortext Publishing Corporation (Iqaluit). Retrieved 2009-01-01.
Jump up ^ Huicochea, Alexis. "Man lifts car off pinned cyclist", Arizona Daily Star, 28 July 2006. Retrieved 21 November 2010.
Jump up ^ Associated Press. "Kansas dad somehow lifts car off 6-year-old girl", 18 December 2009. news.yahoo.com. Retrieved 19 December 2009.
Jump up ^ Greg Auman (2011-06-24). "USF Bulls offensive lineman Danous Estenor lifts car to free trapped man". St. Petersburg Times (Tampa Bay, FL).
Jump up ^ Newcomb, Alyssa. "Superhero Woman Lifts Car Off Dad - ABC News". ABC News. Retrieved 12 January 2016.
Jump up ^ "Oregon man pinned under 3,000-pound tractor saved by teen daughters". Fox News. 11 April 2013. Retrieved 12 January 2016.
Jump up ^ "Shea Heights hero finds strength to lift vehicle off injured boy". CBC News. 28 September 2015. Retrieved 28 September 2015.
Jump up ^ McCrum, Kirstie (11 January 2016). "Teen girl uses 'superhuman strength' to lift burning truck off dad and save family". Mirror. Retrieved 11 January 2016.
Jump up ^ Hoh, JF; Rossmanith, GH; Kwan, LJ; Hamilton, AM (1988). "Adrenaline increases the rate of cycling of crossbridges in rat cardiac muscle as measured by pseudo-random binary noise-modulated perturbation analysis". Circulation Research. 62: 452–461. doi:10.1161/01.RES.62.3.452.
Jump up ^ Grassi, C; Passatore, M (February 1988). "Action of the sympathetic system on skeletal muscle". Italian journal of neurological sciences. 9 (1): 23–8. PMID 2965685.
^ Jump up to: a b c d e f g Liddle DG, Connor DJ (June 2013). "Nutritional supplements and ergogenic AIDS". Prim. Care. 40 (2): 487–505. doi:10.1016/j.pop.2013.02.009. PMID 23668655. Amphetamines and caffeine are stimulants that increase alertness, improve focus, decrease reaction time, and delay fatigue, allowing for an increased intensity and duration of training ...
Physiologic and performance effects
• Amphetamines increase dopamine/norepinephrine release and inhibit their reuptake, leading to central nervous system (CNS) stimulation
• Amphetamines seem to enhance athletic performance in anaerobic conditions 39 40
• Improved reaction time
• Increased muscle strength and delayed muscle fatigue
• Increased acceleration
• Increased alertness and attention to task
Jump up ^ Bracken NM (January 2012). "National Study of Substance Use Trends Among NCAA College Student-Athletes" (PDF). NCAA Publications. National Collegiate Athletic Association. Retrieved 8 October 2013.
^ Jump up to: a b c Parr JW (July 2011). "Attention-deficit hyperactivity disorder and the athlete: new advances and understanding". Clin Sports Med. 30 (3): 591–610. doi:10.1016/j.csm.2011.03.007. PMID 21658550.
^ Jump up to: a b c Roelands B, de Koning J, Foster C, Hettinga F, Meeusen R (May 2013). "Neurophysiological determinants of theoretical concepts and mechanisms involved in pacing". Sports Med. 43 (5): 301–311. doi:10.1007/s40279-013-0030-4. PMID 23456493.
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List of To Kill a Mockingbird characters
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To Kill a Mockingbird is a novel by Harper Lee published in 1960. It was instantly successful, winning the Pulitzer Prize, and has become a classic of modern American literature, widely read in US high schools and middle schools.[1] The story takes place during three years of the Great Depression in the fictional Maycomb, Alabama.
This is a list of the characters:
Contents
1 Primary characters
1.1 Atticus Finch
1.2 "Scout" Finch
1.3 "Jem" Finch
1.4 Dill Harris
1.5 Calpurnia
1.6 Arthur "Boo" Radley
1.7 Judge John Taylor
1.8 Miss Maudie Atkinson
1.9 Robert E. Lee "Bob" Ewell
1.10 Mayella Ewell
1.11 Tom Robinson
1.12 Aunt Alexandra
2 Minor characters
2.1 Jack Finch
2.2 Francis Hancock
2.3 Mrs. Henry Lafayette Dubose
2.4 Mr. Heck Tate
2.5 Mr. Braxton Underwood
2.6 Mr. Horace Gilmer
2.7 Dr. Reynolds
2.8 Dolphus Raymond
2.9 Link Deas
2.10 Miss Caroline Fisher
2.11 Reverend Sykes
2.12 Miss Stephanie Crawford
2.13 Miss Rachel Haverford
2.14 Helen Robinson
2.15 Nathan Radley
2.16 Jessie
2.17 Burris Ewell
2.18 Lula
2.19 Mrs. Grace Merriweather
2.20 Walter Cunningham, Jr.
2.21 Walter Cunningham, Sr.
2.22 Little Chuck Little
2.23 Mr. Dick Avery
2.24 Miss Gates
2.25 Eula May
2.26 Cecil Jacobs
2.27 Tim Johnson
2.28 Simon Finch
2.29 Maxwell Green
2.30 Mr. X Billups
2.31 The Barber Sisters (Miss "Tutti" and Miss "Frutti")
2.32 Mrs. Gertrude Farrow
2.33 Mr. Conner
2.34 Zeebo
3 References
Primary characters[edit]
Atticus Finch[edit]
Main article: Atticus Finch
Atticus Finch is the middle-aged father of Jem and Scout Finch. He is a lawyer and was once known as "the deadliest shot in Maycomb County". Although he was a good shot, he does not like to mention the fact as he does not like the thought of having an advantage over people. He appears to support racial equality and was appointed to represent Tom Robinson, a black man who has been accused of raping a young white woman, Mayella Ewell. The town disapproves of him defending Tom especially when he makes clear his intent to defend Tom Robinson to the best of his abilities. He is portrayed by Gregory Peck in the film adaptation of To Kill a Mockingbird.
"Scout" Finch[edit]
Jean Louise "Scout" Finch, as an adult, is the narrator. She comments on how she could not understand something at the time but now can appreciate it. She gets into trouble with Miss Caroline, her teacher, because she is expected to learn reading and writing her way. She is a tomboy and spends the most of her time with her brother Jem and best friend Dill. To Jem's advice to pretend to be a lady and start sewing or something, she answers, "Hell, no". The hints the narrator gives us about her grown-up life reveal that she has not attempted to change herself to please others.[2]
She matures from age 6 to age 9 as the novel progresses but remains naive and idealistic, despite an increased understanding of human nature and racism in her town. At the beginning of the book, Scout is confused by some of the words and names she hears people directing towards her father, such as "nigger-lover". Being only six, Scout does not know how to handle such situations so she tries to resolve her problems by fighting, or by talking to Atticus about what she has heard. By the end of the book, Scout realizes that racism does exist and comes to terms with its presence in her town. Scout also learns how to deal with others, including the Finch family housekeeper, Calpurnia, and her aunt, Alexandra. Scout is the only one of the novel's primary three children (Dill, Jem, and herself) to see and speak to Boo Radley during the course of the novel and realize that he is harmless, despite her initial fear of him. She also stops a mob that is trying to lynch Tom Robinson by talking to the mob leader, Mr. Cunningham, about inviting his son, Walter, over for dinner. Mr. Cunningham then tells the other mob members to get back in their cars and leave them alone. The members listen, and Scout unintentionally saves Tom Robinson's life. She is portrayed by Mary Badham in the film adaption of To Kill a Mockingbird.
Notable quote: "Until I feared I would lose it, I never loved to read. One does not love breathing." [3]
"Jem" Finch[edit]
Jeremy Atticus "Jem" Finch is Atticus' son and Scout's older brother by four years. Jem matures greatly throughout the course of the novel, much more affected by events than Scout seems to be. Being four years Scout's senior, Jem is seen to have a greater understanding of - and therefore greater difficulty in navigating - the obstacles thrown their way. Jem is seen explaining many things to Scout throughout the novel. Bob Ewell breaks Jem's arm during his assault on the Finch children, subsequently resulting in it being shorter than it had been, in an attempt to protect his sister. He is portrayed by Phillip Alford in the film adaptation of To Kill a Mockingbird.
Dill Harris[edit]
Charles Baker "Dill" Harris is a short, smart boy who visits Maycomb every summer from Meridian, Mississippi, and stays with his Aunt Rachel (Aunt Stephanie in the film). Dill is the best friend of both Jem and Scout, and his goal throughout the novel is to get Boo Radley to come out of his house. The children concoct many plans to lure Boo Radley out of his house for a few summers until Atticus tells them to stop. In chapter 5 of the novel, Dill promises to marry Scout and they become "engaged". One night Dill runs away from his home in Meridian, arriving in Maycomb County where he hides under Scout's bed. When she finds Dill, he tells both Scout and Atticus that he was chained to a wall in his father's basement; later, he confesses he actually ran away because he felt he was being replaced by his stepfather. Before Dill returned to Meridian after the summer, he went swimming with Jem at the Barker's Eddy creek. Scout, unfortunately, was unable to participate, because both boys were swimming naked.
Unlike Scout and Jem, Dill lacks the security of family support. He is unwanted and unloved by his mother and stepfather: "They do get on a lot better without me, I cannot help them any." As Francis (a cousin of Jem and Scout) says, "He hasn't got a home, he just gets passed around from relative to relative." Dill maintains he has no father; he doesn't know where his father might live, or if he will ever come back. He is played by John Megna in the film adaption of To Kill a Mockingbird.
This character is believed to be based on author Truman Capote, a childhood friend of Harper Lee.[4]
Calpurnia[edit]
Calpurnia, nicknamed Cal, is the Finch family's African-American housekeeper, whom the children love and Atticus deeply respects (he remarks in her defense that she "never indulged [the children] like most colored nurses"). She is highly regarded by Atticus. She is an important figure in Scout's life, providing discipline, instruction, and love. She also fills the maternal role for the children after their mother's death. Calpurnia is a mother herself and raised her son, Zeebo, to adulthood. Calpurnia is one of the few black characters in the novel who is able to read and write, and it is she who taught Scout to write. She learned how to read from Miss Maudie's aunt, Miss Buford, who taught her how to read out of Blackstone's Commentaries, a book given to her. Aunt Alexandra despised Calpurnia because Alexandra believed that Calpurnia was not a "maternal figure" for Jem and Scout, especially for Scout.
Calpurnia is a member of the First Purchase M.E. African Church in Maycomb. While Scout always hears her speak proper English, she is surprised to learn that Calpurnia does not do so at church, especially with the uneducated members of the congregation.
While everyone in the novel is filtered through Scout's perception, Calpurnia in particular appears for a long time more as Scout's idea of her than as a real person. At the beginning of the novel, Scout appears to think of Calpurnia as the wicked stepmother to Scout's own Cinderella. However, towards the end of the book, Scout views Calpurnia as someone she can look up to, and realizes Calpurnia has only protected her over the years. She is played by Estelle Evans in the film.
Arthur "Boo" Radley[edit]
Arthur "Boo" Radley is a recluse in To Kill a Mockingbird.
Maycomb children believe he is a horrible person, due to the rumors spread about him and a trial he underwent as a teenager. It is implied during the story that Boo is a very lonely man who attempts to reach out to Jem and Scout for love and friendship, such as leaving them small gifts and figures in a tree knothole. Scout finally meets him at the very end of the book, when he saves the children's lives from Bob Ewell. Scout describes him as being sickly white, with a thin mouth, thin and feathery hair, and grey eyes, almost as if he were blind. During the same night, when Boo whispers to Scout to walk him back to the Radley house, Scout takes a moment to picture what it would be like to be Boo Radley. While standing on his porch, she realizes his "exile" inside his house is really not that lonely.
Boo Radley's heroics in protecting the children from Bob Ewell are covered up by Atticus, Sheriff Tate, and Scout. This can be read as a wise refusal of fame. As Tate notes, if word got out that Boo killed Ewell, Boo would be inundated with gifts and visits, calamitous for him due to his reclusive personality. The precocious Scout recognizes the danger: renown would "kill the mockingbird". Boo Radley is a ghost who haunts the book yet manifests himself at just the right moments in just the right way. He is, arguably, the most potent character in the whole book and as such, inspires the other key characters to save him when he needs saving.
After the Tom Robinson trial, Jem and Scout have a different understanding of Boo Radley. "Scout, I think I'm beginning to understand something. I think I'm beginning to understand why Boo Radley's stayed shut up in the house all this time… it's because he wants to stay inside." (23.117) Having seen a sample of the horrible things their fellow townspeople can do, choosing to stay out of the mess of humanity doesn't seem like such a strange choice.[5]
When Boo finally does come out, he has a good reason: Bob Ewell is trying to murder the Finch children. No one sees what happens in the scuffle, but at the end of it, Ewell is dead and Boo carries an unconscious Jem to the Finch house. Finally faced with Boo, Scout doesn't recognize him at first, but suddenly realizes who he is. Boo Radley is played by Robert Duvall in the film.
Judge John Taylor[edit]
Judge John Taylor is a white-haired old man with a reputation for running his court in an informal fashion and an enjoyment of singing and dipping tobacco. He presides over the Tom Robinson trial showing great distaste for the Ewells and great respect for Atticus. Because of the judge's sympathies for Tom, Bob Ewell breaks into the judge's house while the judge's wife is at church. After the trial, Miss Maudie points out to the children that the judge had tried to help Tom by appointing Atticus to the case instead of Maxwell Green, the new, untried lawyer who usually received court-appointed cases. Judge Taylor knew that Atticus was the only man who would stand a chance at acquitting Tom, or at least would be able to keep the jury thinking for more than just a few minutes. By doing this, Judge Taylor was not giving in or supporting racism. He is portrayed in the film by Paul Fix.
Miss Maudie Atkinson[edit]
Miss Maude "Maudie" Atkinson lives across the street from the Finch family. She had known the Finches for many years, having been brought up on the Buford place, which was near the Finches' ancestral home, Finch's Landing. She is described as a woman of about 50 who enjoys baking and gardening; her cakes are especially held in high regard. However, she is frequently harassed by devout "Foot-Washing Baptists", who tell her that her enjoyment of gardening is a sin. The Foot-Washing Baptists also believe that women are a sin as well. Miss Maudie befriends Scout and Jem and tells them stories about Atticus as a boy. It is strongly implied that she and Atticus have a more than platonic relationship. Also, she is one of the few adults that Jem and Scout hold in high regard and respect. She does not act condescendingly towards them, even though they are young children. During the course of the novel, her house burns down; however, she shows remarkable courage throughout this (even saying that she wanted to burn it down herself to make more room for her flowers). She is not prejudiced, though she talks caustically to Miss Stephanie Crawford, unlike many of her Southern neighbors, and teaches Scout important lessons about racism and human nature. It is important to note that Miss Maudie fully explains that "it is a sin to kill a mockingbird", whereas Atticus Finch initially brings up the subject but doesn't go into depth. When Jem gets older, and doesn't want to be bothered by Scout, Miss Maudie keeps her from getting angry. Maudie is played by Rosemary Murphy in the film.
Robert E. Lee "Bob" Ewell[edit]
Robert E. Lee "Bob" Ewell is the main antagonist of To Kill a Mockingbird. He has a daughter named Mayella and a younger son named Burris, as well as six other unnamed children. He is an alcoholic, poaching game to feed his family because he spends whatever money they legally gain via government "relief checks" on alcohol. It is implied, and evidence suggests, that he was the one who abused his daughter Mayella, not Tom Robinson (the African American man accused of doing so). Although most everybody in town knows that the Ewells are a disgrace and not to be trusted, it is made clear that Tom Robinson was convicted because he is a Negro whose accuser is white. Upon hearing of Tom's death, Bob is absolutely gleeful, gloating about his success. After being humiliated at the trial, however, he goes on a quest for revenge, becoming increasingly violent. He begins by spitting in Atticus' face, followed by a failed attempt to break into the home of Judge Taylor, then finally menacing Helen, the poor widow of Tom Robinson. Ewell later attempts to murder Jem and Scout Finch with a knife to complete his revenge. Boo Radley saves Jem and Scout and it is believed that he kills Ewell with the knife. Heck Tate, the sheriff, puts in the official report that Bob Ewell fell on his own knife and died after lying under a tree for 45 minutes. Ewell is played by James Anderson in the film.
Mayella Ewell[edit]
Mayella Violet Ewell, 19, is the oldest of the eight Ewell children. Before the trial, Mayella is noted for growing red geraniums outside her otherwise dirty home in order to bring some beauty into her life. Due to her family's living situation, Mayella has no opportunity for human contact or love. She eventually gets so desperate that she attempts to seduce a black man, Tom Robinson, by saving up nickels to send her siblings to go get ice cream so that Mayella can be alone with Tom. Her father sees this through a window and in punishment he beats her. Ewell then finds the sheriff, Heck Tate, and tells him that his daughter has been raped and beaten by Tom. At the trial, Atticus points out that only the right side of Mayella's face is injured, suggesting a left-handed assailant; Tom's left arm is mangled and useless, but Bob Ewell is left-handed. When Atticus asks her if she has any friends, she becomes confused because she does not know what a friend is. During her testimony she is confused by Atticus' polite speech and thinks that his use of "Miss Mayella" is meant to mock her. She testifies against Tom Robinson. Mayella is played by Collin Wilcox in the film.
Tom Robinson[edit]
Thomas "Tom" Robinson is an African-American who is put on trial for the rape of a white woman, Mayella Ewell. Atticus is assigned to defend him, and stands up to a lynch mob intent on exacting their own justice against him before the trial begins. Tom's left arm is crippled and useless, the result of an accident with a cotton gin when he was a child. Atticus uses this fact as the cornerstone of his defense strategy, pointing out that the nature of Mayella's facial injuries strongly suggest a left-handed assailant. Tom testifies that he had frequently helped Mayella with household chores because he felt sorry for her and the family's difficult life - a statement that shocks the all-white, male jury. Despite Atticus' skilled defense, the jury's racial prejudices lead them to find Tom guilty. Atticus plans to appeal the verdict, but before he can do so, Tom is shot and killed while trying to escape the prison where he is being held. Tom Robinson is played by Brock Peters.
Aunt Alexandra[edit]
Alexandra Hancock (née Finch) is Atticus' and Jack's sister, married to James "Uncle Jimmy" Hancock. She has a son named Henry and a very spoiled grandson named Francis. Around the middle of the book, Aunt Alexandra decides to leave her husband at Finch's Landing, the Finch family homestead to come stay with the Finches. Aunt Alexandra doesn't consider the black Calpurnia to be a very good motherly figure for Jem and Scout; she disapproves of Scout being a tomboy and wants to make Scout into a southern belle (encouraging her to act more 'lady like').[6] This is the cause of many conflicts between Scout and Alexandra throughout the course of the novel. However, as the trial progresses, Scout comes to see how much her aunt cares for her father and what a strong woman she is. This is especially evidenced by a tea party when Scout is horrified by the racism displayed, and her aunt and Miss Maudie help her deal with her feelings. By the end of the book, it's clear that Alexandra cares very much for her niece and nephew, though she and Scout will probably never really get along.
Minor characters[edit]
Jack Finch[edit]
John Hale "Jack" Finch is Atticus' and Alexandra's younger brother. (He is about 40, which is 10 years younger than Atticus.) Jack smells like alcohol and something sweet, and is said that he and Alexandra have similar features. Jack is a childless doctor who can always make Scout and Jem laugh, and they adore him. He and Miss Maudie are close to the same age; he frequently teases her with marriage proposals, which she always declines. Jack also has a pet cat named Rose Aylmer, who is mentioned during the Christmas visit.
Francis Hancock[edit]
Francis Hancock is the spoiled grandson of Aunt Alexandra. (The son of her son, Henry Hancock.) Every Christmas, Henry and his wife drop Francis at Finch's Landing, which is the only time Scout and Jem see him. Francis lives in Mobile, Alabama, and is a bit of a tattle-tale. He gets along well with Jem, but often spars with Scout. One Christmas, Francis calls Atticus a "nigger-lover," as well as insisting that he was ruining the family and the likes, which infuriates Scout and causes them to get into a fight. Francis lies about his role in it, telling Uncle Jack that Scout started it by calling him a "whore lady", and Jack therefore punishes Scout. However, she explains the full story and charitably persuades her uncle not to punish Francis about it, but to let Atticus think they had been fighting about something else (although Atticus later discovers the truth).
Mrs. Henry Lafayette Dubose[edit]
Mrs. Henry Lafayette Dubose is an elderly woman who lives near the Finches. She is hated by the children, who run by her house to avoid her. Scout describes Mrs. Dubose as "plain hell." A virulent racist, she calls Atticus a "nigger-lover" to his children's faces, and Jem flies into a rage and ravages Mrs. Dubose's camellia bushes. As a punishment, Jem is required to read to Mrs. Dubose each day for a month. As Jem reads, she experiences a fit of drooling and twitching and does not seem to pay any attention to the words. When an alarm rings, Jem is allowed to leave for the day. She extends the punishment for one extra week and dies shortly after letting Jem go for the last time. Atticus informs him that Mrs. Dubose was terminally ill and had become addicted to morphine. By reading to her, Jem had distracted her so that she could break the addiction. In thanks, she leaves him a candy box with a camellia flower in it; Jem burns the box in anger, but is later seen by Scout admiring the flower. Atticus tells Jem that Mrs. Dubose was the bravest person he ever knew, and she was trying to teach Jem the importance of bravery and true courage to endure anything when the situation is hopeless, as in her morphine addiction.
Mr. Heck Tate[edit]
Mr. Heck Tate is a friend of Atticus and also the sheriff of Maycomb County. He believes in protecting the innocent although he doesn't usually show it. At the end of the book, the Atticus and Heck argue over whether Jem or Boo Radley should be held responsible for the death of Bob Ewell. Heck eventually persuades Atticus to accept the theory that Ewell accidentally fell on his own knife, thus saving the harmless, reclusive Boo from the public exposure of a criminal trial.
Mr. Braxton Underwood[edit]
Mr. Braxton Bragg Underwood is a news reporter and a friend of Atticus. He owns and also publishes The Maycomb Tribune. Being a racist, he disagrees with Atticus on principle. He also has a strong belief in justice, as exemplified when he defends Atticus from the Cunningham mob by having his double barrel shotgun loaded and ready to shoot them. He also demonstrates some humanity when he publishes a scathing editorial comparing the killing of Tom Robinson (a cripple) to "the senseless slaughter of songbirds by hunters and children".
Mr. Horace Gilmer[edit]
Mr. Horace Gilmer is a lawyer from Abbottsville, and is the prosecuting attorney in the Tom Robinson case. Mr. Gilmer is between the ages of forty and sixty. Mr. Gilmer has a slight cast with one eye, which he uses to his advantage in trial. Mr. Gilmer appeared to be racist in his harsh cross-examination of Tom Robinson, but it is hinted at that he is in fact going easy on Tom. He and Atticus are not rivals and talk to each other during recesses during the case.
Dr. Reynolds[edit]
Dr. Reynolds is the Maycomb doctor. He is well known to Scout and Jem. Scout says that he "had brought Jem and me into the world, had led us through every childhood disease known to man including the time Jem fell out of the tree house, and he had never lost our friendship. Dr. Reynolds said that if we were boil-prone things would have been different..." (ch. 28). He inspects Jem's broken arm and Scout's minor bruises after the attack from Bob Ewell under the tree.
Dolphus Raymond[edit]
Dolphus Raymond is a white landowner who is jaded by the hypocrisy of the white society and prefers to live among black folks. In fact, he has children with a black woman. Dolphus pretends he is an alcoholic so that the people of Maycomb will have an excuse for his behavior, but in fact he only drinks Coca Cola out of a paper bag to try to hide it. When Dill and Scout discover that he is not a drunk, they are amazed. He shows Scout how sometimes you can pretend to be someone you're not so people will be more understanding of you.
Link Deas[edit]
Link Deas owns cotton fields and a store in Maycomb who employs Tom and later Helen because she does not get accepted by any other employers in the county due to Tom Robinson's legal troubles. He announces to the court (in defense of Tom) at one point in the trial that he hadn't "had a speck o' trouble outta him" in the eight years Tom had been working for him, and gets sent out by Judge John Taylor for doing so. When Bob Ewell starts threatening Helen after the trial, Mr. Deas fiercely defends her and threatens to have Mr. Ewell arrested if he keeps bothering her. He is on Tom Robinson's side during the trial and remains loyal to the family afterward.
Miss Caroline Fisher[edit]
Miss Caroline Fisher is Scout's first grade teacher and is new to Maycomb, Alabama and its ways. She attempts to teach the first grade class using a new system which she learned from taking certain college courses (Jem mistakenly refers to it as the "Dewey Decimal System", which is really how library books are organized.). She is upset by Scout's advanced reading capabilities and believes that Scout is receiving lessons from Atticus. She feels as though Scout is trying to outsmart and mock her. In an effort to standardize the class, she forbids Scout from reading with her father. Atticus asks Scout to step into Miss Caroline's skin. However, he continues to allow Scout to read with him at night so long as she continues to go to school. Miss Caroline has good intentions but proves quite incompetent as a teacher. When Scout tells Miss Fisher that she shamed a student (Walter Cunningham, Jr.) by giving him lunch money, she raps Scout's palms with a ruler (a punishment unheard of in Maycomb). She is also very sensitive and gets emotionally hurt quite easily, as seen when she cries after Burris Ewell yells at her, "Report and be damned to ye! Ain't no snot-nosed slut of a schoolteacher ever born c'n make me do nothin'! You ain't makin' me go nowhere, missus. You just remember that, you ain't makin' me go nowhere!" After the Burris Ewell incident, Miss Caroline is seldom seen and soon forgotten.
Reverend Sykes[edit]
Reverend Sykes is the reverend of the First Purchase M.E. African Church in Maycomb County, where most if not all of the African-American characters go to church. Reverend Sykes forces the congregation to donate 10 dollars for Tom Robinson's family since at the time, Tom's wife, Helen, was having trouble finding work. During the trial, when the courtroom was too packed for the children to find seats, Reverend Sykes lets the kids sit with him up in the colored balcony and even saves their seats for them.
Miss Stephanie Crawford[edit]
Stephanie Crawford is the neighborhood gossip who claimed that she saw Boo Radley from her bedroom standing outside of her cleaned window one night. Crawford is one of the first on the scene after a loud gunshot is heard behind the Radley house. Because she is the neighborhood gossip, it is unwise to think of anything that she says as true, because most of the time it is not true at all. She is a friend of Alexandra Hancock. She lets Miss Maudie live with her when Miss Maudie's house burns down, supposedly in order to steal Miss Maudie's Lane cake recipe. She is thrilled to pass on gossip to the kids about Boo Radley. She claimed to have witnessed Bob Ewell's threatening Atticus at the Post Office corner as she was returning from the local Jitney Jungle grocery store.
In the film, she takes the place of Rachel Haverford and is now Dill's aunt.
Miss Rachel Haverford[edit]
Miss Rachel Haverford is Dill's aunt and the Finches' next door neighbor. She drank neat whiskey heavily after seeing a rattlesnake coiled in her closet, on her washing, when she hung her negligee up. Even though she can be very hard to deal with, she truly does love her nephew. Her family name, in the legends of Maycomb County, is synonymous with jackass. She is also a Southern Belle.
In the film, she is not a character and Miss Stephanie takes her place as Dill's aunt.
Helen Robinson[edit]
Helen Robinson is the wife of Tom Robinson. She is spoken about a few times. She has three children. Employed by Link Deas following the death of her husband, she is repeatedly harassed by Bob Ewell when traveling to work. Upon learning of this, Deas threatens Ewell, forcing him to stop. She is an example of how one person's actions can have an effect on a lot of people and she elucidates the hardships that surround the Tom Robinson case.
Nathan Radley[edit]
Nathan Radley is the brother of Arthur "Boo" Radley and another difficult character to understand in To Kill a Mockingbird. When the children try to catch a view of "Boo" late one night through a window, he shoots over their heads with a shotgun (albeit thinking he was aiming at a black person). Nathan also cements up the knothole in which Arthur leaves little gifts for the children. On the other hand, he helps Miss Maudie by saving some of her belongings when her house is on fire. He is more present than his brother, but equally mysterious.
Jessie[edit]
Jessie is Mrs. Dubose's black nurse. She is the woman who shoos the children out when Mrs. Dubose has her fits, and she seems to care enormously for Mrs. Dubose. When Jem is forced to stay reading to Mrs. Dubose, Jessie kindly leads Jem and Scout to the door when Mrs. Dubose's alarm goes off. The rumors about Mrs. Dubose concealing a gun about her person involves Jessie; the book says "and even if Mrs. Dubose missed, her girl Jessie wouldn't".
Burris Ewell[edit]
Burris Ewell is a son of Bob Ewell and a younger sibling of Mayella Ewell as well as the first antagonist of the novel. Burris is described as being chiefly antagonistic of Little Chuck Little and his teacher Miss Caroline Fisher. He comes to the first day of school, but departs just as everyone else in his family does. Burris is also poor. He has live lice in his hair. Burris also scared his teacher Caroline Fisher. He behaves rudely when she tells him to go home, wash his hair, and come back clean the next day. He refuses, and a student explains to Miss Caroline that Ewell children don't attend school. All they do is show up for the first day, get marked down on the register, and then they miss the entire school year until the first day of the next year. His famous quote was, "Report and be damned to ye! Ain't no snot-nosed slut of a schoolteacher ever born c'n make me do nothin'! You ain't makin' me go nowhere, missus. You just remember that, you ain't makin' me go nowhere!" As of Scout's first year of school (the first grade), Burris has repeated the first grade three times. Burris is also like his father and is very belligerent.
Lula[edit]
Lula is an African-American woman with a dislike for white people. She doesn't like the idea of Calpurnia bringing Atticus Finch's children, Jem and Scout, with her to church and tells her so but is overruled by the other congregants. According to James Zeebo, Calpurnia's son, Lula's said to be, "a troublemaker from way back, with fancy ideas and haughty ways." She's threatened with being "churched" (subjected to church discipline) by Reverend Sykes.
Mrs. Grace Merriweather[edit]
Mrs. Grace Merriweather is the producer of the play in which Scout plays as a ham. She tells Everett that "the ladies of the South Maycomb Alabama Methodist Episcopal Church are behind him one hundred percent." She is mostly known for her devotion to the church and is widely held as the most devout lady in Maycomb; however, like many of her peers, she is very hypocritical and loves to gossip with all the other women.
Walter Cunningham, Jr.[edit]
Walter Cunningham, Jr. is a child who is almost as old as Jem but is in Scout's class. He lives on a farm. He is too poor to even pay off a 25-cent debt because the Great Depression hit his poor family hard. He doesn't take money because his family can't pay people back in cash. His father paid Atticus for his service for something a while back with some goods. Walter is invited over to the Finches' house once, after engaging in a fight with Scout, where he covers up all of his dinner with molasses, much to Scout's vocal dismay. This teaches Scout a lesson in humility and compassion.
Walter Cunningham, Sr.[edit]
Walter Cunningham, Sr. is Walter Cunningham Jr.'s father. He appears only twice, once at the beginning of the story when he has to pay off the debt to Atticus (Walter Cunningham Sr. was his client) by giving him firewood, vegetables and other supplies. He also leads the mob that comes to lynch Tom Robinson the night before the trial. Only when Scout talks to him about his son and how much he owes to Atticus does he reconsider and call off the mob. Scout innocently shames him because Scout reminds him of all the things that Atticus has done for him and for Maycomb County. After the verdict is given in the trial, Atticus tells Jem that one of the Cunninghams had changed his thoughts about Tom and pleaded that Tom was not guilty to the jury.
Little Chuck Little[edit]
Little Chuck Little is a student in Scout's first-grade class who has the mindset of an adult. His real name is Charles. He is depicted as chiefly antagonistic of Burris Ewell. He is presented in the novel when Miss Caroline is frightened by Burris' lice. He warned Miss Caroline that if Burris wasn't released from class, he might try something that would put their classmates at risk. When Burris starts advancing on Little Chuck after his warning/veiled insult, Little Chuck's hand moved to his pocket (implying that he was going to pull out a knife) while saying, "Watch your step, Burris. I'd soon's kill you as look at you. Now go home." Scared by Little Chuck's bravery and his implied knife, Burris retreats. From this we see, through the narrative view of Scout, his gentlemanly attitude and how it calms Miss Caroline down. Little Chuck may be even more intelligent than originally meets the eye, as he easily could have been bluffing about the aforementioned implied knife to scare Burris into retreating.
Mr. Dick Avery[edit]
Mr. Dick Avery is an overweight neighbor who tells Jem and Scout that dramatic changes in the weather are caused by disobedient and misbehaving children. After it snows, they build a snowman that resembles him. Mr. Avery can also be seen in the story pushing a mattress out of a window when Miss Maudie's house catches fire. The kids, including Jem and Scout, always waited for him to do something interesting. For instance, Jem claims that one night he urinated from his front porch in an impressive arc.
Miss Gates[edit]
Miss Gates is a third grade teacher at Scout's school who insists that America isn't prejudiced like Hitler's Germany. Despite this, Scout has heard her say that the blacks need to be taught a lesson after Tom's trial.
Eula May[edit]
Eula May is Maycomb's most prominent telephone operator. She sends out public announcements, invitations, and activates the fire alarm. She announced the closing of schools when it snowed and announced the rabid dog that entered Maycomb. Also, Eula May knows everybody in the town because of her unique job.
Cecil Jacobs[edit]
Cecil Jacobs teases Scout and Jem at school. Scout almost gets into a fight with Cecil over the trial of Tom Robinson. Scout beats up Cecil Jacobs because he says Atticus is a "Nigger Lover." He gives a current event on Adolf Hitler and later frightens Scout and Jem on their way to the Halloween pageant. He and Scout then pair up at the carnival. At the Halloween pageant afterwards, Cecil was a cow. He hints that black people are not as good as white people while talking about Hitler during current events. He also tends to take jokes too far. However importantly he shows how prejudice is passed on from parent to child.
Tim Johnson[edit]
Tim Johnson is a dog belonging to Harry Johnson (a character in the book who is mentioned once but is never seen). He is infected by rabies in chapter 10 and goes mad, putting everyone in the town at risk. Atticus is forced to shoot Tim Johnson before he reaches the Radley House or attacks anyone. When Atticus shoots the dog, his excellent marksmanship is revealed to Scout and Jem (his nickname used to be One-Shot Finch). The dog's body is collected by Zeebo.
Simon Finch[edit]
Simon Finch is the founder of Finch's Landing. He is referred to in the first chapter of the book, being a direct ancestor of Atticus. He is a Cornish Methodist, and emigrated from England to avoid religious persecution, landing in Philadelphia before settling in Alabama. He was married, with one son, eight daughters. He is also an apothecary.
Maxwell Green[edit]
Maxwell Green is the new lawyer in town. He is normally the judicially-assigned defense attorney but Judge Taylor assigned Tom Robinson's case to Atticus to give Tom Robinson a better chance.
Mr. X Billups[edit]
Mr. X Billups who is seen only once in the book, going to the trial, is described as a "funny man". X is his name, and not his initial. He was asked repeated times what his name was until he signed it. X was the name he had been given when he was born because his parents marked his birth certificate with an X instead of a name.
The Barber Sisters (Miss "Tutti" and Miss "Frutti")[edit]
The Barber Sisters (Miss Sarah, nicknamed "Tutti" and Miss Frances, nicknamed "Frutti") are maiden sisters who live in the only house in Maycomb with a cellar. They were originally from Clanton, Alabama; and are rumored to be Republicans. Besides their Yankee ways, both sisters are deaf (Tutti completely deaf; Frutti uses an ear trumpet), and had a Halloween prank pulled on them by some "wicked" schoolchildren (Scout claims she was not included) who put all of their furniture in their cellar.
Mrs. Gertrude Farrow[edit]
Mrs. Farrow is a lady in the missionary society who visits the Finch house occasionally.
Mr. Conner[edit]
Mr. Conner is mentioned early on in the book. He was locked in an outhouse by "Boo" Radley and his friends. After taking the teenagers to court, Mr. Conner accused them of "disorderly conduct, disturbing the peace, assault and battery, and using abusive and profane language in the presence and hearing of a female." He added the last charge after claiming that the teens had "cussed so loud he was sure every lady in Maycomb heard them."
Zeebo[edit]
Calpurnia's eldest son, Zeebo, was taught how to read by Calpurnia. Zeebo is one of just four people in First Purchase Church who can read, so he is the vocal leader, leading hymns in their church by "lining"—reading a line of verse and having the congregation repeat it. He is also the garbage man of Maycomb, and took away the dead rabid dog, Tim Johnson. When Lula, a fellow church member tries to make Scout and Jem feel bad for attending church with Calpurnia, Zeebo welcomes them with open arms.
References[edit]
Jump up ^ "What Kids Are Reading: The Book Reading Habits of Students in American Schools", Renaissance Learning, Inc., 2008. Retrieved on July 11, 2008. See also "What Kids Are Reading: The Book Reading Habits of Students in American Schools Archived 2012-03-14 at the Wayback Machine., Renaissance Learning, Inc. 2010. Retrieved on May 1, 2011. where To Kill a Mockingbird appears at number 2.
Jump up ^ "To Kill A Mockingbird Guide at studentshare.net; Release Year: 2017".
Jump up ^ "Edmond Public Schools - Edmond Public Schools" (PDF). Archived from the original (PDF) on 2015-02-13.
Jump up ^ Minzesheimer, Bob (December 17, 2007). "'Kansas' imagines Truman Capote-Harper Lee rift". USA Today. Retrieved June 3, 2018.
Jump up ^ "Arthur Radley (Boo) in To Kill a Mockingbird".
Jump up ^ Lee, Harper (1960). To Kill a Mockingbird. United States of America: Warner Books. p. 81.
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