Car-heater patent image dated

On November 28, 1893, the same patent date appeared in later reproductions of the original image for Margaret A. Wilcox’s car-heating invention, confirming the grant date associated with U.S. Patent No. 509,415. This kind of documentary duplication matters because it strengthens the historical record for an invention that has often been summarized more than it has been studied in depth.

Patent images are more than illustrations; they preserve the language, date, and formal recognition of an inventor’s claim. In Wilcox’s case, the dated patent image reinforces her role in the early history of vehicle heating and helps anchor later interpretations of her achievement in a primary-source artifact. The confirmation is especially important because women inventors have often been under-cited or folded into simplified historical narratives.

This date also situates Wilcox’s work within a crucial period of technological transition. Rail travel and mechanized transport were expanding rapidly, and the problem of passenger comfort was becoming increasingly visible. Her patent image therefore stands not only as proof of inventorship but as a symbolic record of a woman asserting technical authorship in an era when such recognition was rare. The continued reproduction of the patent image has helped keep her contribution visible in discussions of transportation history and women’s innovation.