When Jacob W. Davis patented the use of rivets on pants to secure seams from ripping in 1873 he may have opened the flood gates to a barrage of patent filings that aspire to offer similar improvements to workwear. The most curious of these patents awarded was filed by Cheang Quan Wo in late 1874 in San Francisco. It is important to note Levi Strauss's business was and is headquartered in San Francisco.
The drawing accompanying the application shows a man with the front part of his head shaven and the back part tied into a long ponytail to indicate he was a Han Chinese. He would have kept his hair this way so as to be able to return home to China where people of Han ancestry were required by law to wear their hair in a queue.
He is shown wearing suspender waist overalls with pocket openings reinforced with additional material and stitching. The New York Public Library (Mid-Manhattan Library), which catalogs a physical print of the drawing (marked Apr. 24, 1875) suggests the wooden tub behind the subject as a wash tub although I wonder if we can rule out the possibility of it being a rice bucket.
Also of interest in the specific reference to previously proposed methods of seams reinforcements on pants in the section of the application where applicants usually address similar intellectual properties. Wo writes, perhaps through the attorney who filed the patent application, "I am aware that seams have been re-enforced by sewing over them separate and independent pieces to prevent ripping, but this is not my invention. By my device the re-enforcing lap, instead of being a separate and independent piece of goods sewed to the garment, is a part and parcel of the body of the garment, and cut in one piece with it, thus not only avoiding the necessity of a separate re-enforcing piece, but also avoiding one seam, which would be necessary to secure a gusset as usually cut."
In the coming days I will explore various patents related to improvements in workwear and perhaps even attempt to answer if Jacob Davis sparked an intellectual property protection trend in workwear well before jeans became fashion.