I'm sure links to this article have been posted before, but here it is again.
First a quote from the article:
"Wild T-3 theodolites replaced the Parkhurst, which had been in service for about 25 years, in 1952. Early fears that these small optical reading theodolites were unstable proved unfounded. Some observers found the T-3's stubby gun sight pointers inadequate for night work and to resolve the problem taped beer can/bottle openers openers to the top and bottom of the telescopes. Fortunately, this piece of equipment was never in short supply on parties. Later illuminated finders, similar to those found on Parkhursts, were added."
Geodetic Surveying 1940-1990
(You've come a long way baby) By. Joseph F. Dracup ASPRS/ACSM(1994)
Link to Article
"Fortunately, this piece of equipment was never in short supply on parties"