Tonometer

Tonometer

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Description
An optical tonometer determines intraocular pressure by measuring the resistance of a cornea to indentation. A German professor introduced the basic form in 1862. William McLean (1876-1966), a homeopathic surgeon affiliated with the New York Ophthalmic Hospital, argued that his patented design offered several improvements over the Schiotz: it was more easily read, and there was no need to change weights. Inscriptions on the box of this example read “McLean Tonometer” and “E. B. Meyrowitz, INC. / LONDON-NEW YORK-PARIS”.
Ref: William McLean, “Method of and Means for Measuring the Hardness or Softness of Eyes,” U.S. Patent 1,291,050 (Jan. 14, 1919).
William McLean, “Some Experimental Investigations Concerning Intra-Ocular Pressure,” Journal of Ophthalmology, Otology and Laryngology (1914).
V. Mueller & Co., Surgeon’s Instruments, Office and Hospital Equipment (1916), p. 3.
Location
Currently not on view
Object Name
Tonometer
Other Terms
Tonometer; Medicine
maker
E. B. Meyrowitz, Inc.
Measurements
case: 1 1/8 in x 6 in x 3 3/4 in; 2.8575 cm x 15.24 cm x 9.525 cm
tonometer: 5 1/4 in x 2 3/4 in x 1/2 in; 13.335 cm x 6.985 cm x 1.27 cm
ID Number
1977.1223.026
catalog number
1977.1223.026
accession number
1977.1223
Credit Line
R. N. Taylor, M.D.
See more items in
Medicine and Science: Medicine
Data Source
National Museum of American History
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