|WWI artillery vehicle, with factory camouflage applied|
From Frank Parker Stockbridge, Yankee Ingenuity in the War. New York: Harper and Brothers, 1920—
[During World War I] Yankee ingenuity found application in the devising of methods of putting on the camouflage with the utmost speed and efficiency. In the gun carriage plant of the American Car and Foundry Company, for instance, I watched the girls in khaki overalls spraying camouflage on the finished caissons and wheels one afternoon. The paints of different colors, in huge tanks, were deposited by means of a gigantic reproduction of the air brush, used by artists everywhere.
The main office of the American Car and Foundry Company was located at 165 Broadway in New York. Beginning in June 1917, the company's Detroit production facility was contracted by the US Government to produce 10,970 artillery vehicles at a rate of one hundred per day. A peculiar innovation of these is that a brightly-colored disruptive camouflage pattern (see photo above) was airbrushed onto these vehicles as part of their manufacture. It's also interesting that the exact same camouflage pattern was applied to each of them.
The three photos below (along with a number of others) were published in 1919 in a book titled The American Car and Foundry Company in Khaki: Its Production Achievements in the Great War, which was produced and distributed by the company. Shown below are views of the camouflage being applied by women workers in the factory's paint shop (as described above by Stockbridge), the outdoor storage of thousands of these (awaiting shipping instructions), and a crated vehicle ready to ship.