Original linen-backed patent lithograph for A. Dunbar's improvement of a hypodermic syringe, one page, 14.25 x 10.25, April 3, 1888. The syringe features a barrel that has a portion of one side cut away, and is lined with a graduated transparent tube to enable the proper amount of the drug to be injected. The top border reads: "A.D. 1888. April 3. No. 4942. Dunbar's Complete Specification." The lower border features the printed text: "London. Printed by Darling and Son Ltd. for Her Majesty's Stationery Office. 1888" and "Malby & Sons, Photo-Litho." The right border reads: "This Drawing is a full-size reproduction of the Original." In fine condition, with a trimmed top edge.