I have spent a large amount of time doing research at the National Archives, for my Along the ET&WNC series of books. I can shed some light on the question posed in the Tank car 99 thread, but since this is much more far reaching than that one question, I decided to make a new post.
First of all, the National Archives has the "stuff" from the Interstate Commerce Commission. The 1916 Valuation is a tremendous tool for seeing what a railroad had at that time. I use 1916 as that is the date it was done for the ET&WNC, and it is the approximate date for the entire valuation, though for some RRs it was several years later.
The following was what is there as far as rolling stock for the ET&WNC. I am not at home, so all of this is off the top of my head. I may leave out something.
There is a master list of all the freight and passenger cars, plus locomotives, with numerous facts and figures on each class. That is number, length, width, capacity, average tare weight, with notes if there are cars found that did not match the list provided by the RR. Mow is a separate sheet.
In the case of the ET, though not for all RRs, there is a detail set of paperwork. In this instance, the inspector started at Johnson City, the westernmost end of the line, and headed east. Each car he found, he measured it, and made a detailed sheet on it. After that, if he found a comparable car, he made a new sheet saying "same as #___". No further detail. Sometimes the detail sheet had measurement discreprencies from the master sheet, but not too often.
Additional info was on the detail sheets, including brake type, coupler type, diameter of truss rods, height of wheels, and other stuff that I am not remembering off the top of my head.
The passenger equipment had number of seats, type of heat, and other assorted info, including number and measurements of the window sashes.
All of this stuff was considered important for establishing the cost of replacement in case of need. That was the whole purpose of doing the VALUATION. RRs were inflating the value of the property, or deflating it, whichever, for various purposes, including taxation.
A national valuation put everyone on an equal footing for tax purposes.
After the valuation, in certain years, the RRs had to file paperwork, if I remember correctly, a D-558 form, showing changes made to the company since the Valuation. One was in 1927, another in 1932, another in 1937, and then more often thereafter. IF you do not have access to the company records, these forms will show the changes, in broad strokes.
Unfortunately, the NA has only cataloged the updates for the larger railroads. The archivest and I did a little hunting and found the one for the ET&WNC. I had the company records, but having the government forms filled in some holes for me. I was able to put together a list of all cars the ET owned after about 1910, which ended up being between 300 and 400 cars, much more than originally thought. Many of these cars were rebuilt in the 20s, and came out of the shop looking very different, with the same number.
Another wonderful research tool the NA has is the Annual Reports to the ICC. Each year a booklet was filled out and sent in, and rolling stock was shown in blocks of boxcars, flats (platform) cars, etc. The form shows cars added, retired, and totals. For some railroads, there was another sheet that showed the various classes of cars by capacity, ie 30,000, 40,000 and 50,000 lb capacity. If you have some idea of what you are looking at, you can track changes to the roster year by year.
I will say that if you plan to go to the NA, plan several days for the job. Working there requires you to follow certain rules, and allow a full day to actually get to see what you go in looking for. The wheels of figuring out what you want are slow, and they only pull materials at certain times of the day. If you are prepared for that, things will go smoothly.
I will answer questions if anyone has any, but I will close by saying that not all RRs have the same depth of detail. The ICC tended to toss some things in the 70s if the railroad had been closed and gone for decades. Thus not all RRs have the same depth of material. I was lucky in that the ET still has a section in existence, thus they kept it all. The subisidiary Linville river was not so lucky.
Hope this answers some questions.
Johnny Graybeal
