Can someone point me to an on-line (or in-print) source for information about the smokestacks designed by Issac Congdon, and made famous by the South Park engines.

I'm trying to correlate the designs that Congdon installed on early Union Pacific locomotives, and the time frame involved. He started with UP in 1866, and retired in 1885. He died in 1899 as age 66 years.

Apparently the narrow gauge Brooks 2-6-0s of 1881-1882 are the most notable examples of his most famous design, which was patented in 1884.

http://utahrails.net/steam/steam-notes.php#congdon

Don Strack
http://utahrails.net/

here is the patent if you have not found it yet:

http://www.google.com/patents?id=EEpCAA ... on&f=false

he had a lot of other interesting patents as well