This instrument is known as a 'Kater Azimuth Compass'. It was made by Thomas Jones in England and arrived in Australia with Governor Brisbane in late 1821. It was probably used at Australia's first permanent observatory at Parramatta, New South Wales. The compass was designed by Henry Kater a friend of Brisbane's and while at Parramatta Brisbane conducted experiments for Kater using invariable pendulums also made by Thomas Jones.

Kater had joined the British Army in 1799 and was sent to Madras, India where as an ensign he did surveying work with William Lambton. In 1811 while still engaged in the survey he devised the prototype of this azimuth compass which incorporated a mirror that allowed the reading of scales at the same time as observing a distant object through the sighting vane. In 1814 he was elected a Fellow of the Royal Society of London where he took a special interest in the design of standard weights and measures.

This azimuth compass was made sometime between 1811 and 1821 making it one of the earliest examples of this design of azimuth compass in the collection. The compass also matches another Kater Azimuth Compass in the collection (H9918) which may be the prototype of this instrument. This instrument remains of national significance due to its pioneering role in Australian science and its association with Australia's earliest astronomers. It is also of international significance due to its association with early nineteenth century astronomical instruments and their makers.

References
Holland, J., 'Pioneer of Precision; Captain Henry Kater, FRS', http://www.usyd.edu.au/museums/whatson/exhibitions/kater1.shtml
Lomb, N., 'Earnshaw's Excellent Timekeepers', in Davison, G., Webber, K., 'Yesterday's Tomorrows; the Powerhouse Museum and its precursors 1880-2005', Powerhouse Publishing, 2005
Forwarded to H. M. Secretary of State by Despatch, No. 141, 1847, Federation and Meteorology, http://www.austehc.unimelb.edu.au/fam/1541.html
Macmillan, D. S., The Kater family, 1750-1965, The Kater family?, Sydney, 1966

Geoff Barker, August, 2007

Thomas Jones
Thomas Jones was born in 1775 and by 1789 was working for one of the most respected scientific instrument makers of the eighteenth century Jesse Ramsden. Some time after his term with Ramsden he set up his own successful business in Charing Cross, London before going on to be elected as a Fellow of the Royal Society in 1835 and assist in the formation of the Astronomical Society.

Jones's also had a long association with Henry Kater as he constructed compasses and pendulums to Kater's designs. Jones was in turn helped by Kater who communicated his innovations in instruments to the Royal Society before he was elected a Fellow.

References
King, H., C., The History of the Telescope, Dover Publications, New York, 1955
Holland, J., 'Pioneer of Precision; Captain Henry Kater, FRS', http://www.usyd.edu.au/museums/whatson/exhibitions/kater1.shtml

Surveying equipment, Kater azimuth compass and cover, wood / glass / metal / paper, used at Parramatta and Sydney Observatory, made by Thomas Jones, England, 1811-1821

Compass of a type known as a Kater azimuth compass; the body of the compass is formed by a squat metal cylinder, with a glass lid. A hinged frame (the sight) is screwed to the side of the metal cylinder, the hinge enabling the top part to rest on the glass lid or be upright.

Under the glass lid is a green ring on which numerals and scale marks have been written (the compass card). This ring is screwed to two metal arcs forming an elipse. The metal arcs are supported by metal plates, arranged in cruciform and fixed with a screw at the centre.

A socket used to support an eye piece is screwed to the side of the cylinder opposite the sight frame, but the eye piece is missing. Observatory stock number 231.

The compass has a circular white paper cover.
The compass card (ie the green ring) has the name of the maker written on it.

Designed: Kater, Henry;

Made: Jones, Thomas; Charing Cross, England; 1811 - 1821


Used: Brisbane, Thomas Makdougall; Sydney

Owned: Brisbane, Thomas Makdougall; Sydney

Manufacturer's name and address written on compass card above north marking, handwritten in black ink "Thomas Jones; No.62, Charing Crofs, London".
Inventor's name and date written on compass card below south marking, handwritten in black ink "Cap.n H. Kater; Invenit 1811".

H9956

58 mm

57 mm