top of page

© Microscope History all rights reserved

Schmalcalder Most Improved Microscope, 1810-26


This is the larger of two versions of a form of microscope, made (or rather, retailed) by C.A. Schmalcalder to a pattern called after W. & S. Jones. It was based on the 'Universal Compound Microscope', devised by George Adams Jr. and described in his 1787 book Essays on the Microscope. This was, in turn, inspired by Benjamin Martin's 'Universal Microscope' of the second half of the 18th century. After George Adams' death in 1795, his firm was continued by his brother, Dudley Adams. Within a few years, however, William and Samuel Jones bought the copyright to Adams' books, stock and workshop instruments. Hence, Adams' microscope was renamed 'W. & S. Jones Most Improved' and advertised as such in 1798. It was the best microscope of the pre-achromatic era, which summarized in a way the structural evolution of the English microscope over the length of the 18th century. However, it was far from perfection and extremely expensive, and with the introduction of the achromatic objective it was replaced by Lister-limb and Bar-limb microscopes. 

The microscope seen here is signed on the folding tripod base 'Schmalcalder 82 Strand London'. Charles Augustus Schmalcalder (1781 - 1843) was an inventor and optical instrument maker. He is famous for inventing the prismatic compass, which he made with great workmanship. He was born Karl August Schmalkalder in Stuttgart, Germany. He came to England in about 1800, where he worked in partnership with his son John Thomas Schmalcalder. On his retirement in 1839 the business was continued by his son ( Schmalcalder the elder worked in London at 6 Little Newport St. (1806-7), Strand (1812), 82 Strand (1810-26) & 399 Strand (1827-40) (collection.sciencemuseum).

The 'Jones Most Improved' model was most likely the first microscope type to be employed for serious research in geology, chrystallography and optical mineralogy. 

Selected references: MHS 35727,

bottom of page