Introductory lecture to the course of physiology in Kings College, London, 1869 / by Wm. Rutherford.

  • Rutherford, William, 1839-1899.
Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: Introductory lecture to the course of physiology in Kings College, London, 1869 / by Wm. Rutherford. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    1] the changes it undergoes when we look at near or distant objects absolutely determined. Nerve force, which until lately was supposed to travel with such wonderful rapidity that quick as thought actually became a proverb, has, by means of Helmholtz's myograph, had the rate of its transmission along a nerve accurately estimated; and it turns out that, after all, this mode of energy moves with snail-like slowness when compared with the rate at which light and electricity travel. The movements which take place in the respiratory and circulatory systems are now being studied by means of numerous instruments of great ingenuity. We no longer trust our easily misled sense of touch when we want to accurately ascertain many obscure facts with regard to the pulse. In performing an experiment upon the circulatory system, we no longer estimate the force of the heart's action by merely feeling the pulse, or by observing the distance to which the blood is projected from a divided artery : we accurately measure the force and record the movements of the heart by means of suitable ap- paratus. These various instruments have been called '•'instruments of precision, inasmuch as they have rendered definite what could be only conjectural, or at best doubtfully ascertained, before their introduction. A great feature in many of them is the employment of a graphic method, by means of which the facts ascer- tained through their aid may be recorded. Thus we have the myograph, for recording the movements of muscles ; the spirograph, for the respiratory move- ments; the cardiograph, kymograph, and sphygmo- graph, for registering movements which take place in the circulatory system. By means of these instru- ments, movements are recorded on revolving cylinders or on flat surfaces, so that a tracing, or writina, indi- eating the character and extent of the motion, may be