U.S. Vending Machine Co., Washington, D.C., pat. 1921, 10 1/2". Based on the picture of this model in Silent Salesmen Too, page 274, I've always thought it was a neat machine and wanted to own one someday. I like glass-cased machines like the Kone Klutch stamp vendor and the Mansfield and Colgan's Taffy Tolu gum machines, which showcase the machines' inner structures and workings, and this is a member of that class.
According to Silent Salesmen Too, this is one of the earliest machines designed to vend the "new" (back then) coiled stamps issued by the post office. The instructions on the machine's top explicitly tell the customer to not deposit money if the stamp rolls are empty, and the glass front and sides make it easy for the customer to tell if they are. The fact that the glass is beveled adds---in my opinion---a touch of class that goes beyond what's needed to function. It's an impressive machine that looks old and completely solid. The top and base of this model are made of thick cast iron, and picking it up is like picking up a small boat anchor.
The example above is 100% original.
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