made in London
This brass compound microscope was made in London between 1836 and 1838. Andrew Pritchard (1804-1882) was the third British optician to sell achromatic microscopes (the first being George Dollond, the second William Tulley). After an apprenticeship with his uncle, also an instrument maker, Cornelius Varley (1781-1873), Pritchard set up on his own in London in 1827. He experimented with the jewel lens, demonstrating that he was interested in improving the optics of the simple microscope. However, it is for his compound instruments, especially the so-called 'Pritchard mode' for which he is remembered.
The microscope probably cost fifteen guineas new, according to a catalogue of 1837. The compound instrument comes with a low power objective, and a dividing objective (only part of this survives) by Pritchard; a 1/8th inch objective by Hugh Powell, 4/10th inch objective by Smith & Beck, and a 1/8th inch objective by Wray. Accessories include a second body tube, plain and mechanical stages, Nicol prism polarise and analyser; parabolic illuminator, and a candle holder which attaches to the base of the microscope. The mahogany box is not shown.
The type of microscope which is now known as the Pritchard model was first announced in 1834. However, the receipt of the seven guinea Powell 1/8th inch objective, dating from 1840, survives, made out to 'The Rt Honble the Countess of Caledon', as do Pritchard's own undated instructions to her about the use of his three component objective.
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