The apparatus for the estimation of blood-pressure which I desire to present has the following features to recommend it:
Extreme simplicity; the avoidance of all ground joints, cocks, valves and complicated mechanisms.
Absence of metal parts to amalgamate the mercury.
Ease of manipulation; only one hand being required to work the apparatus, the other being free to feel the pulse or manipulate the stethoscope in auscultation.
Cheapness; there being no expensive parts or construction, this apparatus can be sold for one-half the price of the cheapest instrument at present on the market.
Portability; it may be taken apart readily, carried in any convenient bag and quickly put together again for use. The entire apparatus weighs fourteen ounces.
This apparatus consists of:
1. Wooden base with supports for small glass mercury cistern and for upright 300 mm. scale graduated in millimeters. Lying in a groove in this