"Halley’s Diving Bell The diving bell made its appearance in the 16th century, under the name campana urinatoria, and accounts can be found of its use in the 17th century to recover sunken treasure. One adventure raised gold, chains and other…
Ebony frame with ivory scale having anchor engraved at its centre, calibrated in degrees, micrometer adjustment & Vernier to 1' arc. 1 green shade, 2 red shades. Double pin-hole site with moveable cover across a single pin-hole. Forerunner of the…
4 different sets of balances. Chinese balances in bamboo carrying cases known as Dotchins. They were used in the Chinese market place for weighing gold currency that consisted of irregular pieces stamped with their purity; violin-shaped wooden case…
Brass and wooden model of escapement with 60 second face. Pendulum ( ABDNP200022b ) fits on rear. Holes on right of base probably for small pulley wheel, now missing. Dial marked in seconds and labelled every 10 seconds. Escapement wheel 152 mm…
Instrument for showing that a compass needle not only points to magnetic north but if freely suspended will point into the ground. This later phenomenon is known as the 'dip' of the compass needle. Horizontal scale 0 -90 in 1/20 on either side of N…
'Dollond's achromatic telescope of two and three quarter inch aperture and 4 feet focus, with polar axis, on a mahogany stand, 2 astronomical and 1 terrestrial eyepiece and a divided object glass micrometer.' The instrument in the University's…
Universal equatorial instrument. 18th century instrument for positional measurement of stars with telescope mounted on an equatorial mount having finely graduated scales. Brass with 18" circles. Originally made by Sisson. Afterwards divided anew,…