Zero Stock-Vintage Precision Aneroid Barometer Made by Negretti & Zambra London
SOLD Fine example of rare precision Aneroid barometer made by well known scientific instruments maker Negretti & Zambra from London. In 1939 after a long research the company Negretti & Zambra have established a totally new design of aneroid barometers consisting in two sets of four exhausted diaphragm boxes for high accuracy. The barometer face has a 5 inch silvered dial with the (28-32 inch column of mercury) range and a very thin and light tubular hand. An anti-parallax mirror is fitted on the dial behind the knife edge of the pointer to avoid distortions. The barometer bezel has room for a extra magnifying glass. The setting adjustment consist of a quadrant and pinion which in effect rotates the whole movement and eliminates the errors introduced when the setting is made. The anodized brass barometer comes in a well fitted mahogany case 6 ½ in x 6 ½ in x 4 in. The mahogany case has some minor discoloration of the lid. The barometer is still very accurate and shows differences in atmospheric pressure.