Are You a "Gurley" Man?
The level (Gurley catalog #372) is of unknown date of manufacture. The serial number is GA1722, which may help you in determining its exact age.
The level is in very good condition (some paint has chipped off of the barrel, and the finish shows some wear around the the thumbscrew posts), given that it was a working level until sometime after February 27, 1989, the last date of calibration indicated on the sticker on the inside of the box lid from the now-defunct Carl Heinrich Company of Cambridge, Massachusetts.
The box (mahogany?), given its years of field use, is in decent shape, and what appears to be the original leather strap is intact and sturdy. The metal nameplate on the top has the matching serial number of the level on it as well.
The top of the barrel of the level is stamped "W. & L.E. GURLEY TROY, N.Y., U.S.A." at the rear half and the serial number "GA1722" on the front half.
I've seen similar levels listed on-line for anywhere from $300 to $600. I'm asking $375 [or B.R.O. - ed.] for this one.
UPDATE (FWIW): The information on this page gives the year of manufacture for this level as 1941.
A frequently asked question is, "How old is my Gurley instrument?". In some cases this is a very simple question to answer, in others much detective work is needed. The Gurley company was started in 1845 so the range of possibilities is quite large. As a simple guideline for determining age, the following ideas are offered.
For instruments made after 1908, generally the first two digits of the serial number represent the year of manufacture. As an example, a serial number of 29288 would have been made in 1929. An exception to this is that not all levels follow this scheme and there is no apparent definitive scheme for levels.
There are some instruments that have a letter coding according to the following:
W A N T G U R L E Y
0 1 2 3 4 5 6 7 8 9
It is believed that most instruments, if not all, that use this coding were made for a government contract(s).