(_4_) Compilation for the permanent record. The men chosen as field inspectors were old and experienced railroad engineers. As far as possible, they were assigned for a short period to office inspection, then they were sent into the field, after which they worked at the computation of values; so that each man was engaged on many different phases of the work, and handled the notes of many of his fellows, and no one man made up one complete appraisal, except as specially noted. _Making the Inventories._—Office inspection, or the preparation of inventories, was assigned to parties usually of one or two experienced men with from two to four younger engineers as assistants in the computing-room. These men went to the general offices of the railroad companies and made a complete examination of maps, profiles, bridge and building records, records of motive power, rolling stock, etc. In short, they prepared, as far as it was possible to do so, a complete inventory of every building, structure, or piece of property owned by the road; they took off complete abstracts of real estate and right-of-way records; they noted principal yards and terminals, and secured maps of such as were most complex, or furnished lists of such maps and records as were most essential for the field men, and they made as complete a report as possible of the corporate history of the road and the general condition of its engineering records. No effort whatever was made to examine or audit the financial books of any company, or to secure from such books any data as to cost of property; the work was entirely limited to the listing of physical property. Most of the railroad companies co-operated, and gave access to their records; one or two filled in the forms; a number had practically no records, and only one or two companies withheld information. Requests for blue prints of large yards and terminals, and of plans of standard structures were generally granted cheerfully, and, although there was no such spirit of co-operation as was shown later by the Wisconsin roads, much labor was saved by the data furnished. The result of the office inspection was the filing of inventories, which were generally quite complete, the securing of maps and plans, the gathering of data as to prevailing prices of labor and material, and the securing of some very valuable cost data as to special structures and classes of structures. All inventories were made up for roads, or for divisions of roads, with each class of property listed separately, for example, station buildings, interlocking plants, bridges, etc., so that, if necessary, any special class of inspection might be assigned to one man, while to others could be assigned the remainder of the work on that particular road or division.