Re: Need help with Vacuum Brake Equipment

I don't have any great amount of info on Eames brakes except to note that DSP&P used them early on before switching to the Westinghouse Automatic system in the early 80's. From various South Park books I have gotten the impression was that they worked fairly well on short (less then 20 cars) trains but as trains got longer they weren't able to keep up. There were also problems at higher elevations because the difference between the (lower) outside pressure and the (partial) vacuum the system generated was less, making the brakes less effective.

"A more likely competitor[to Westinghouse] was the Eames Vacuum Brake Company of Boston. in its system, a steam-operated 'ejector' took the place of a pump and drew air out of a bowl-shaped vessel under each car when a control valve was opened. That caused an India-rubber cover to be drawn inward by the greater atmospheric pressure on its outer face, and the motion of the diaphragm was transmitted by rods and cams to the brakes."

"The Iron Horse" by Henry B. Comstock (1971) pg127

Mr Comstock goes on to describe tests at Burlington Iowa in 1886 in which both Westinghouse & Eames brakes were less than desired and a 3rd type flat-out failed and goes on to say the Eames Co. "finally settled for a market limited to urban railways, including the New York elevateds."

So I'd look for data in publications of the 1870-86 period, (perhaps coverage of the Burlington trials?) and on sources that have to do with the New York El.

Hope that helps a bit,

hank