A very rare example of a Troy New York sureying instrument, circa 1840, signed by block engraving on the silvered compass face, "O. Hanks Troy NY PATENT". The case lid retaining an important example of an original Oscar Hanks trade label which shows examples of his surveying instruments and other wares.

The compass bow measures 12" in diameter; the compass needle is 5.5" overall. The compass has two thumb screws which hold the bow feet to the base of the compass; both of these screws are replicated from originals. The needle ring is cutaway to expose two bubble levels, one is lacking (but replaceable). The compass retains an original finish throughout including the silvered compass face. The specialized vernier needle retains a beautiful bluing. The original flat dovetailed walnut case has fixtures to hold the bow, compass box and hub. The staff retains the original brass ball & Socket joint and swaged iron point. The outfit is complete and in very fine condition.

Possibly the most unique American compass sight vane design is that of Troy New York maker & designer Julius Hanks. His 1833 patent states, in part, …"The circular band with openings therein for sight…." [Cite: Ellsworth, Henry L., Digest of Patents Issued by the United States from January 1790 to January 1839, Washington 1840]. The bow compass is described, "The sights in the circumferentor instead of rising vertical in the usual way, are in the form of a vertical circle furnished with slots and holes which enable the surveyor to take in elevations and depressions which cannot be sighted by the ordinary instrument."

The term "hoop compass" was named by Charles Smart in his book, American Surveying Instrument Makers Since 1700. He coined the phrase prior to the discovery of early Hanks family advertising where the term "...Bow Compass and Circumferentor..." was advertised in the year 1835. Additional patented and uncommon features incorporated on this compass include the vernier needle, and the sliding weight on the needle. Note attached to the end of the needle is s silver vernier; this feature offered a means to divide a degree to smaller parts (as in the rare minute compasses). The sliding needle weight was developed to compensate for varied magnetic dip as the compass was used in various regions.

Bow compasses were made by Oscar Hanks from 1835 to 1845 only. There are currently 11 known examples. This is the ONLY example complete with the original staff, ball & socket and case. The Oscar Hanks label in an important part of this offering; the label offers valuable information by illustrating variations of Hanks instruments and other wares; this is the only known example of this trade label. I am offering this instrument from my private collection; it is one of very few American designed patent instruments, a fine example of a Hanks Patent Bow Compass.

TERMS OF SALE:

• We offer free shipping and insurance within the contiguous United States, by standard ground-service UPS or standard USPS.
• We ship on Friday of each week.
• All special delivery requests, including international shipments, are at the added expense of the buyer.
• All Objects Guaranteed as Described, and, are Sold with a Limited Three Day Money Back Guarantee.
• Payment by Pay Pal or bankable check, required within 10 days of auction completion.
• Please email for additional images or information.
• Questions? E-mail or call (319)-895-0506 (Central Time Zone).
• Please include lot number and title with all correspondence.

  Thank you.