https://c8.alamy.com/comp/RCE1CW/digest-of-agricultural-implements-patented-in-the-united-states-from-ad-1789-to-july-1881-agricultural-machinery-patents-quot-v-xquot-i-1-g-armstrong-improvement-in-gang-plows-jp-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-allen-james-t-james-titus-united-states-patent-office-new-york-printed-by-j-c-von-arx-RCE1CW.jpg