Quain's stethometer, late 19th century.

Made:
1871-1900 in London and London and
supplier:
Coxeter

Quain's stethometer in case, by Delolme and supplied by Coxeter, London. Sir Richard Quain (1816-1898) devised the stethometer to measure the difference in mobility of each side of the chest, as an aid to diagnosis.