https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/13964613![Engineering: a large cogwheel, front and side elevations. Coloured drawing, 1875, by [].](https://images.rawpixel.com/image_social_square/cHJpdmF0ZS9sci9pbWFnZXMvd2Vic2l0ZS8yMDI0LTAyL2xyL3djdGhuOHcyYXYtaW1hZ2UuanBn.jpg)
Engineering: a large cogwheel, front and side elevations. Coloured drawing, 1875, by [].
Original public domain image from Wellcome Collection
Public DomainFree CC0 image for Personal and Business use