ALT Patent drawing of a hard hat design from E.W. Bullard's US Patent No. 1,699,133, dated January 15, 1929, above an array of modern hard hats in various colors.

ALT Image of Margaret Knight's patent no. 220,925 for a paper bag machine alongside a photo of a young girl working in the textile industry

ALT Photo of Bessie Blount teaching a soldier how to write with his foot and her patent no. 2,550,554 showing a device that helps people feed themselves

ALT Black and white photo of inventor Edward Bullard with drawings from his patent no. 1,699,133 for a "hat crown" or hard hat covering

ALT Sarah Boone's patent no. 473,653 with the words "Inventors at Work" and a photo of a class of African American women in a sewing class in the background

ALT Patent number and drawing for Sarah Sewell's combined washing machine and teeter totter with a photo of children doing the washing in the background

ALT Black and white photo of Jan Matzeliger with patent art from his invention and a shoe factory in the background

ALT Black and white photo of Frank Zybach with the patent drawing of his irrigation system and wheat in the background

ALT Black and white photo of Lee with his patent number and drawing and with loaves of bread in the background

ALT Patent number and drawing for a paper bag machine with a child mill worker in the background

ALT Patents from various inventions against a blue background with the title "Inventors at Work"