A rare brass orrery, Benjamin Martin, London circa 1765

the hand-cranked movement contained in a horizontal brass drum, the top engraved with an un-named compass rose and with a silvered ring engraved with a calendar, zodiacal indications and signed B. Martin Invt et Fecit Londini, with six armatures radiating from a central post and gilt-brass sun, each with an ivory sphere and representing the planets, Saturn, Jupiter and the Earth with their own separate orbiting moons, the drum mounted on a turned pillar and folding tripod scroll supports, together with a lunarium with brass Earth and ivory Moon on a mechanical frame with silvered rings for angle-of-orbit, lunar date and calendar/zodiac, and a tellurium with 3-inch globe by James Ferguson mounted on a mechanical frame; in a later fitted mahogany case

Illustrated and described in Scientific Instruments by Anthony Turner and Harriet Wynter, page 46 Fig. 47. 

For further details see Benjamin Martin and the development of the Orrery by John R Millburn in The British Journal for the History of Science, Vol.6, No.24,1973.

Some tarnishing and discolouration to brass, ring to Saturn repaired, otherwise generally good condition. Modern felt-lined mahogany case in good condition. With replaced ivory-handled crank key and a case key.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

Benjamin Martin (1704-1782) was born at Worplesdon, Surrey, the son of a farmer. He moved to London and by 1756 was Free of the Goldsmiths' Company and established in Fleet Street as an instrument maker. In 1757 he purchased the globe making interests of James Ferguson. In partnership with his son, Joshua Lover Martin, from 1777, he retired in 1780 but within two years he died and the business was made bankrupt.