Gardiner Brown's tuning fork (C'), English(?), 1841-1920 Four tuning forks invented by Gardiner Brown, c 1841-1930. Audiology 1841-1930
Tuning fork (G), made by Philarmonic(?), English, first half of 19th century Tuning fork, c 1800-1850. Audiology 1801-1850
Gardiner Brown's tuning fork (C°), made by Arnold and Sons, English, 1851-1895 Four tuning forks invented by Gardiner Brown, c 1841-1930. Audiology 1851-1895
Gardiner Brown's tuning fork (C) made by Down Bros., English, 1874-1900 Gardiner Brown's tuning fork Audiology 1874-1900
