A very fine Schmalcalder's type greencard prismatic compass, made in London by Edward Wrench c.1835. The compass card is signed 'Edwd. Wrench, 6 Grays Inn Terrace, London'. Edward Wrench (1797-1866) was working as a scientific instrument maker and optician from 1822 to 1852, trading from 6 Grays Inn Terrace from c.1829 to 1852. In 1829 his name appeared in court proceedings at the Old Bailey in connection with the theft of several pairs of spectacles from his Grays Inn Terrace shop. The London Post Office Directory for 1843 also listed his business at 6 Grays Inn Terrace.
This compass is in the style of the first prismatic compasses by Charles Schmalcalder (1781-1843), who patented his innovative design in 1812. Featuring a beautifully hand-drawn green compass card, bronzed finish brass case with push-fit lid, prism and vane sights, azimuth mirror, red and green filters, manual card brake, and a transit lock which operates when the sights are folded down. The Wrench compass is much larger than most compasses of this type and date, at 120mm diameter - almost all the Schmalcalder's Patent types were just 70mm diameter. The compass comes complete with its original, very well made, early Georgian style fitted leather case.
The compass is also signed in gilt lettering on the rear of the sighting mirror by the retailer, 'Husbands & Sons, 8 St Augustine's Pd, Bristol'. Husbands must have acquired and resold this compass long after it was originally made by Wrench - as they only started trading several years after Wrench had ceased making scientific instruments. Husbands were established in Bristol in 1858 by Henry Husbands (c.1824-1900) and William Clarke (1810-1873), trading from their shop in St Augustine's Parade. They became well known as 'Scientific Instrument Makers, Manufacturing Opticians and Photographic Dealers'. The business name was changed to H. Husbands in 1870, then to H. Husbands & Sons in 1893.
Edward Wrench (1797-1866): was working as a scientific instrument maker and optician in London from 1822 to 1853, trading from 6 Grays Inn Terrace from c.1829 to 1852. In 1829 his name appeared in court proceedings at the Old Bailey trial of James Doherty in connection with the theft of several pairs of spectacles from the Grays Inn Terrace shop. The London Post Office Directory for 1843 also listed his business at 6 Grays Inn Terrace. Edward Wrench is known to have made telescopes, globes, barometers, compasses, and mathematical instruments. His family continued the business, trading as John Wrench & Son until 1922.
Husbands & Sons, Bristol (1858-1910): the business was established in Bristol in 1858 by Henry Husbands (c.1824-1900) and William Clarke (1810-1873), trading from their shop in St Augustine's Parade. Both Husbands and Clarke initially worked as senior journeymen for Thomas Davies King (1819-1884), a Bristol optician and manufacturer of microscopes and other scientific and engineering apparatus. King operated shops at 2 Clare Street and 8 St. Augustine’s Parade. Around 1856-1858, Husbands and Clarke took over Thomas King’s St Augustine's Parade business. Beginning on April 24, 1858, advertisements from Husbands and Clarke appeared weekly in the Bristol Mercury. By August, 1860, the partners were doing well enough to donate one of their barometers to the Bristol Royal Infirmary. Husbands and Clarke exhibited their scientific instruments at the 1862 International Exposition in London, including 'optical instruments', and a 'traversing theodolite and portable equatorial'. At the 1867 Clifton Industrial Exhibition, 'Messrs. Husbands and Clarke contributed a valuable collection of microscopes and other scientific instruments, together with some galvanic batteries, and a miniature locomotive worked by electricity, an ingenious and interesting piece of mechanism'. Husbands and Clarke dissolved their partnership on October 4, 1870, with Husbands taking over the debts, and the business name was changed to H. Husbands. The name changed again to to H. Husbands & Sons in 1893. Henry Husbands died in 1900 and the business was continued by his sons until 1910.
Charles Augustus Schmalcalder (1781-1843) was one of the most significant figures in the development of the compass. His patent design of 1812, which introduced the idea of using an optical prism, combined with a sighting vane, to improve accuracy when taking bearings, is still in use today. Schmalcalder's innovation was a development of the work of Henry Kater. In 1811 Kater developed a design using a mirror and sighting vane. His design was then manufactured by Thomas Jones. Schmalcalder, who also knew Thomas Jones, is believed to have seen Kater's new compass at Jones' premises, and this gave him the idea for his own prismatic version. Schmalcalder moved swiftly to have prototypes of his own design made by Jones, which he then went on to patent. Winning the race to patent his innovation, Schmalcalder's compass completely eclipsed Kater's earlier design. Between 1812 and 1826 (when the patent expired) Schmalcalder's Patent compasses were manufactured by third party makers, like Thomas Jones, and sold from Schmalcalder's premises, first at 82 The Strand, London, and later from 399 The Strand, London. Schmalcalder continued in business until around 1840, with his design being used uncredited by many other makers, such as Simms, Cary, Jones, Wrench, and Troughton after the patent expired in 1826. No doubt as a result of this, Schmalcalder fell on hard times, dying in poverty in 1843 and being buried in the Strand Union Workhouse cemetery.
Further information on Schmalcalder, Kater and the early development of the prismatic compass, can be found at trademarklondon.com
Condition:
In excellent condition, and full working order. The compass finds North very well. The compass card is in exceptionally good condition. The glass, sighting vane, and prism are in excellent condition. There is some minor wear to the original bronzed finish of the brass case. The compass comes complete with its original, early Georgian style fitted leather case, which is in very good condition, with just the lower part of the strap missing.
Dimensions: 120mm diameter x 30mm height
(Leather case: 125mm x 150mm x 40mm)
