Slater, IA: Junction Tower: C&NW vs. Millwaukee

(Satellite, judging from the photo, the tower was in the southwest quadrant.)

Chicago & North Western Historical Society posted
Someone wanted to see a photo of Slater, Iowa.  Here is the only one we have from the archives of our C&NW Historical Society.  It was taken by Charles Stecher around 1917.  Since he was a C&NW signals instructor, he was not all that interested in photographing depots.  Signal systems were his thing.  Thus, the photo.  Slater is located Between Des Moines and Ames.  What line crossed the C&NW at Slater as a tower is seen at left?

[As many comments indicated, Milwaukee was the crossing railroad.]

Norman Cheville: Chicago Milwaukee St Paul & Pacific RR As I understand it, the town of Slater was created when livestock shippers were being charged high shipping prices; the depot and yard were created in Slater for cheaper shipping rates to Chicago.

C&NW was the north/south route, and Milwaukee was the east/west route. Both routes are now abandoned.

1913/13 Slater Quad @ 62,500