It provided shelter..

for the head end brakeman. 

Other use for a "doghouse"

Thats funny you should ask. As I was working in the train room last night my mind wondered off into the operations of the layout if and when I get the track laid. I have a Raildriver and was thinking about driving a train with a video camera in front of the loco. Then I started thinking about how it would be cool to mount a camera in the doghouse on a tender. Then I could see behind me and maybe spot cars without even seeing the layout. As in from the dispatchers desk area.Just a thought but your post reminded me of it.LOL

Rob Teed

It's where I spend.....

...............a lot of time when the Honeydew's take a back seat to the RR!!!

Peter

Wasn't that one of the

Wasn't that one of the functions of a caboose?

In (and out of) the doghouse

The caboose didn't do much for the head end brakeman.  Without a doghouse, the head end man would have to scramble over the coal load to shelter inside the locomotive cab.  There is some speculation (I don't know if there is any official data or not, but the correlation seems quite strong) that Southern Ry. installed doghouses on freight engines with stokers, so that the brakeman would not have to risk getting caught in the stoker to get shelter.

Cab Size Matters

A large factor on several roads was cab size.  Some roads had rather small cabs on their steamers, and there simply wasn't much room for a third person in the cab.  Other roads had a more generous cab design that included seating for two people on the fireman side of the loco.

I've heard arguments that some roads put doghouses for the brakeman because it gave better visibility of the train, but the few doghouses I've seen (and been in) didn't seem to bear that out from what I could see.  I couldn't determine any advantage there.

-Jack