U.P. blow-off (blow-down) details,

[nobullchitbids]

U.P. had an interesting and (as far as I know) unique type of blow-off/blow-down apparatus on its modern steam locomotives such as mountains, northerns, &c., and this was retrofitted into at least a few Harriman mikes. These appliances consisted of two units attached to the firebox on the engineman's side and connected to the cab via a pipe which bifurcated at a 45-degree tee. PSC makes a casting which can be adapted to model these devices, although the casting is a little crazy and can use some disassembly and rebuilding.

My questions are:

1) Did the pipe contain rodding common to operating most blow-off cocks, or did these appliances work on air or steam?

2) (Most important) When a locomotive, such as a Harriman, was rebuilt with this kind of blow down, what did the fireman's side look like? Did U.P. simply keep the older blow-off***and rodding there, or were additional modifications made?

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