I visited the National Archives back in 1985 to copy 1917 era ICC valuation information for some Texas railroads.  A guy at the Interstate Commerce Commission had a 4-drawer file cabinet full of information, including accession numbers, that was necessary at the time to provide to the National Archives.  The archivists needed the correct ID numbers for them to locate the material.  He said that there was no information concerning valuation for locomotives or freight cars in his indexes.

A friend and I spent five days copying information from the ICC valuation books.  These had measurements of EVERY structure for EVERY railroad in the country.  We did not see any locomotive or freight car information at all.  The books were 5" X 7-1/2" in size and contained detailed measurements, handwritten in pencil on greenish paper, of every depot, outhouse, stock pen, bridge, trestle, etc. on the railroad.  I copied 3,700 pages (including some large blueprint maps of track plans) using my copy stand and 35mm Nikon copy camera.  There were NO books of photographs in the collection.  However, I know that some must have existed - I have a book of 700+ photos of I&GN structures that exactly corresponds to the measured structures in the ICC valuation books.

A. T. Kott