Here we have some Northern Pacific Time Inspector's Forms & Envelope.

                                  Above; Front of Card.  At Bottom the Back.

Watches were to be inspected at regular intervals by a Watchmaker / Time Inspector. The Time Inspector would give out a "Loaner" Watch, inspect & if needed, adjust & / or repair the watch before handing it back with an Inspection Report. Each Railway had different criteria for what kind of watch was "acceptable" but generally followed the guidelines set down by a commission in the 1890's which became "The Bureau of Railroad Time Service".  These 'guidelines' were changed several times, excluding some types & accepting others but generally included only 18 & 16 size, 'Lever Set' Watches & Watches of certain Manufacturers & Jewel Counts, (first 15 Jewel, then 17 Jewel & by 1930 only certain 19, 21, & 23 Jewel, 16 size, Open Face Models were acceptable.  

A bit after 1900 most Lines had phased out the Hunter Case Watches in favor of  the Open Face Watch Movement & after 1908 only Double Roller Movements that were Adjusted to 5 positions & stamped so, along with the Jewel Count on the Back Plate, were acceptable.