You are in the CarrTracks website Picture Gallery.
I think Jack laid over one day in Amarillo to get some pictures of the stock yards and some other industrial photos. Looking north, this picture shows the Santa Fe yard. Downtown Amarillo is to the left, north and west of the Santa Fe yard. This is just about the same location where Interstate 40 goes over the yard today.
Before the CTC machines were installed in the Amarillo dispatchers office, this was modern dispatching. Before the 1930s the dispatcher would have been tapping out code on a telegraph key to send train orders to various station agents along the line. Now with a modern telephone system, the dispatcher can talk directly with agents along the line. What you don't see in the picture is the little foot pedal and bar that the dispatchers holds down with his foot when he wants to talk. The dispatcher is sending a train order and writing in a book as he speaks. He writes the exact words of each train order. When each station agent repeats back to him the content of the train order, he will underline each word as the agent reads it. After the train order has been fulfilled, the two trains have met or whatever, the dispatcher will use a crayon to mark through his copy in the train order in the book. Phones, pens, and crayon, the modern tools of the dispatcher.
Beneath the train order log book is a huge sheet of paper called an "on sheet." In the middle is a column with all of the names of the train order offices. To the left and right are columns and rows of blank places for the dispatcher to fill in vital information about each train. Each train gets its own column. After a train passes a station, the agent will call the dispatcher to report the time when the train was by that particular station. The station agent records the train number and time on a record sheet at his station. He then reports the "OS" (on sheet report) of the train number and time to the dispatcher. The dispatcher then records in the appropriate column (the train) and row (the station) the time reported.