The blood-pressure and its variations in the arterioles, capillaries and smaller veins / by Charles S. Roy and J. Graham Brown.

  • Roy Charles S. (Charles Smart)
Date:
[1878?]
Catalogue details

Licence: Public Domain Mark

Credit: The blood-pressure and its variations in the arterioles, capillaries and smaller veins / by Charles S. Roy and J. Graham Brown. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    [From the Journal of Physiology, Yol. II. No. 5.] THE BLOOD-PRESSURE AND ITS VARIATIONS IN THE ARTERIOLES, CAPILLARIES AND SMALLER VEINS. By CHARLES S. ROY, M.D., George Henry Lewes Student, and J. GRAHAM BROWN, M.D. (PI. X.) In experimental work of this kind much depends upon the reliability of the method of investigation employed, and we consider it necessary, on that account, to describe somewhat minutely the different apparatus which we made use of in the course of our observations. We believe that with the various arrangements we employed for measuring the height of the blood-pressure in the peripheral vessels, numerical data of very considerable accuracy may be obtained. The more important conclusions, however, which may be drawn from the results of our experiments, are of a kind which would not be directly affected even by a much wider margin of error than that which it is believed may reasonably be ascribed to the method of enquiry. N. v. Kries1 is apparently the only observer who has attempted to measure, more or less directly, the pressure of the blood in the capillaries. His measurements were made on the vessels of the human skin, that portion on the back of the distal phalanx of one of the fingers immediately behind the nail being found most convenient for his purpose. The method he employed consisted in pressing, by means of weights, a small glass plate of known area upon the portion of skin selected, and finding the weight required to produce a distinct whitening 1 N. v. Kries. “ Ueber den Druck in den Blutcapillaren dcr mcnschlichen Haut.” Ber. d. sacks. Ges. d. Wissensch. 1875, and Ludwig’s Arbeiten. PH. II. 25