The 35th Engineer Regiment was formed at the request of General Pershing and was headquartered at Camp Grant, Rockford, Illinois. This regiment, composed of three battalions of about 225 men each, formed in September, 1917 and shipped out to France in January 1918. Their mission was to repair the freight cars of the severely damaged French railroad in order to move supplies to the fighting forces at the front.
The first repaired car rolled out of the shops in March 1918. After that, the 35th repaired and built box cars, flat cars, low side gondolas, high side gondolas, ballast cars, tank cars and refrigerator cars.
After assembling 224 new cars in that first month of March 1918, the 35th Engineers improved their output to 2,370 cars in September of 1918. As the war wound down and demand lessened, so did the output of the 35th, and in May 1919, the last of the 35th left La Rochelle, France and what became known as Camp Pullman.
During their 17 months in France, they built over 17,000 cars. The last of the cars was still in use in the early 1970s.
My grandfather, Robert Whitefield Bullen, II. Bullen wrote of his experiences riding in a 40 and 8 boxcar: "Left Le Havre Oct. 23 for South France loaded in boxcars so crowded you couldn't think and weren't allowed to have a light or stick our heads out the door."
The engineers of the 35th developed a better design, based on the XM type boxcar in use in the United States: