old UNION PACIFIC "RAILROAD SIGNALING" photograph booklet

Seems like this 44p. 5-1/4" x 7-3/4" staple bound booklet would have been a promotional sort of item meant for train travelers if not intended for the general public, though it certainly could be both. Within the nicely embossed matching covers featuring the UNION PACIFIC OVERLAND shield logo are full color photographic plates (with brief captions) of all sorts of railway signal equipment (and trains) on each LH page, with text and keywords on the opposite RH pages providing further explanation of the equipment pictured and how it operates to keep railroads operating safely. Pic 2 is inside the front showing copyright date of 1910, pic 3 is the last page featuring a U.S.A. map showing Union Pacific train routes of the time, pic 4 is a representative photograph page showing the interior of something called an "Instruction Car".