A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine (1885) (14594877707)

Identifier: manualofhumanphy01land (find matches)
Title: A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine
Year: 1885 (1880s)
Authors: Landois, L. (Leonard), 1837-1902 Stirling, William, 1851-1932
Subjects: Physiology Histology
Publisher: Philadelphia, P. Blakiston, Son, and Company
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library



Text Appearing Before Image:
, contraction of muscle. Landois Gas-SphyglUOSCOpe.—A superficially placed artery communicates itsmovements to the overlying skin, and also to any freely movable body in contactwith the skin. In this instrument (Fig. 55) a thin layer of air over the pulsatingartery, a, is enclosed by means of a thin piece of metal, which ia so adjusted thatits concave side forms a tunnel of air over the artery. The narrow space betweenthe metallic wall, b, and the skin, a, is filled with ordinary gas, one end of themetal shield being connected by means of a tube, y, with the gas-supply, while tothe other end there is attached by means of a short piece of caoutchouc, x, q, abent glass-tube, t, with a very small aperture which acts as a gas-burner. Thegas is allowed to flow through the apparatus at a low pressure, and is so regulatedthat the flame, v, is only a few millimetres in height. The flame rises isochron-ously with every pulse-beat, and the dicrotic beat in the normal pulse is quiteobservable.
Text Appearing After Image:
Fig. 55. Landois gas-sphygmoscope—a, skin over artery; b, metal plate ; p, y, gas;x, q, caoutchouc tube attaching glass gas-burner, t to b. Czermak photographed a beam of light set in motion by the movements of thepulse. Hsemautography.—Expose a large artery of an animal, and divide it so thatthe stream of blood issuing from it strikes against a piece of paper drawn in front 136 THE PULSE-CURVE. of the blood-stream. A curve (Fig