Gurley Level Serial Numbers

• Gurley Level Serial Numbers
• Gurley Post Office Gurley Al

A frequently askedquestion is, 'How old is my Gurley instrument?' In somecases this is a very simple question to answer, in others much detectivework is needed.

The Gurley company was started in 1845 sothe range of possibilities is quite large. As a simple guidelinefor determining age, the following ideas are offered.For instruments made after1908, generally the first two digits of the serial number represent theyear of manufacture. As an example, a serial number of 29288 wouldhave been made in 1929. An exception to this is that not alllevels follow this scheme and there is no apparent definitive scheme forlevels.There are some instruments thathave a letter coding according to the following:WA N T G U R L E Y01 2 3 4 56 7 8 9It is believedthat most instruments, if not all, that use this coding were made for agovernment contract(s).For earlierinstruments dating them can be quite difficult. One way is to gothrough old Gurley catalogs and look for matches and attempt to narrowthe age to a range of years. Another method is to look for hiddenmarks where someone may have dated the instrument when it was beingmade. These hidden marks can be difficult to locate and it is notrecommended that you tear apart your instrument.

Also, some ofthese hidden marks may be the results of later repair work.There are a coupleof significant design changes that can also help to date Gurleyinstruments. In 1880 Gurley switched from hand engraved plateswith fancier script to mechanical pantograph for engraving. Also,'Troy NY' was moved to the North position.

In 1885Gurley adopted the spring opposed tangent screws and the 'straightA' telescope standards predate 1885.Another thing tolook for are early patent marks on certain parts of the instruments suchas Beaman's stadia arcs, latitude bubbles, and auxiliarytelescopes. These dates would show up on specific parts forseveral years after the initial patent.Another method toobtain approximate dates is to compare a picture of the Gurley shops onthe label in the case with pictures of known dates.

Presentedbelow as thumbnails are 10 pictures of the Gurley shops that range from1871 to 1921. These pictures are from various manuals, catalogs,letterheads and billheads that can be dated. Some of thedifferences in the pictures are very obvious and others are not soobvious.

The differences to look at include the following:angle of view of building, size of the building, number of buildings, isthere a flag, where is the tip of the flag, are there balconies on thethird and fourth floor, does the third floor balcony have a cover, isthere a horse drawn cart, and is there an awning on the ground floorentry?Determiningthe exact age of an instrument can be a very time consuming andfrustrating task, but these general guidelines may be useful toyou.

NMAH Surveying & Geodesy Gurley Browse by MakerMeneely &Oothout (see Meneely)Phelps &Gurley (see Gurley)Roach &Warner (see Roach)GurleyWilliam Gurley (1821–1887) studied civil engineering at RensselaerPolytechnic Institute, worked for Oscar Hanks, a surveying instrument maker inTroy, New York, and then went into partnership with Jonas H. Phelps, anotherlocal instrument maker.

Lewis Ephraim Gurley (1826–1897) worked for Phelps& Gurley, earned a B.A. From Union College, and then rejoined the firm. The Gurley brothers took over the firm in 1852, began trading as W. Gurley, and were soon the largest manufacturer of engineering and surveying instruments in the United States. Several factors contributed to their success. They established a factory rather than a craft workshop, practiced a strict division of labor, hired workers who were relatively unskilled, advertisedwidely, and offered instruments at competitive prices.

Their Manual of thePrincipal Instruments Used in American Engineering and Surveying, published from 1855 to 1921, was a catalog of their instruments and an intelligent explanation of how they were to be used.The design of Gurley instruments remained remarkably stable for many years, making it difficult to determine the date of a particular instrument. But thereare some important clues. Since the signatures on the early Gurley instrumentswere cut by hand, the letters have V-shaped trenches, and their lines are ofvarying width. By contrast, the signatures on Gurley instruments made after 1876 were done with an engraving machine, and thus have lines with vertical walls and uniform width.

The Gurleys introduced serial numbers in 1908, with the first digits indicating the year of manufacture, and the latter digits indicatingproduction rate. Thus, transit #9296 was the 296th Gurley instrument made in1909.

Gurley Level Serial Numbers

Gurley was incorporated in 1900, with all the stock held by the family. Teledyne purchased the firm in 1968, began trading asTeledyne-Gurley, and phased out the production of surveying instruments soonthereafter.Ref:William H. Skerritt, 'W.

Gurley Post Office Gurley Al

Gurley’s EngravingMachine,' Rittenhouse 11 (1997): 97–100.Skerritt, Catalog of the Charles E. Smart Collection of Antique Surveying Instruments (Troy, N.Y., 1996).Collection.