The elements of physiology : containing an explanation of the functions of the human body : in which the modern improvements in chemistry, Galvanism, and other sciences, are applied to explain the actions of the animal economy / translated from the French of A. Richerand ... by Robert Kerrison.

  • Richerand, A. (Anthelme), 1779-1840.
Date:
1808
Catalogue details

Licence: Public Domain Mark

Credit: The elements of physiology : containing an explanation of the functions of the human body : in which the modern improvements in chemistry, Galvanism, and other sciences, are applied to explain the actions of the animal economy / translated from the French of A. Richerand ... by Robert Kerrison. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    endeavoured to explain every thing by the diameter of ves- sels, their length and curvature, the compound reason of the action of solids and impetus of fluids. We shall see, in treating on different points of physiology, Avhat defective theories were the result of these applications, and particu- larly of the force of action in the heart. AH who followed the same tract ran counter to each other: yet we cannot reasonably doubt but that effects take place in the animated machine that relate to the laws of hydraulics. The brain, for example, has continual occasion to receive a great quan- tity of arterial blood, endued with an increase of vitality, t by a recent passage through the substance of the lungs; but a too rapid afflux, a too sudden access of this fluid might change its structure. Nature, therefore, as we shall men- tion, in the circulation of blood in the brain has employed all the hydraulic means in her power to weaken the force of its access, and diminish the velocity of its passage. Has man ever more happily applied the laws of hydrau- lics than nature has done in the construction of that surprising rete mirabile that the internal carotid arteries of quadrupeds form in the basis of the cerebrum? Without this disposition, the impetus of blood carried by the arteries with a force superior to that which animates the heart of man, and unable to overcome the resistance that is made by its own gravity, would have infallibly deranged the structure of this delicate organ. As to the application of mathematical sciences and calcu- lations, we must say, that few things being absolutely cer- tain in physiology, and many barely probable, calculation can only be used on probabilities, and elements sought after in facts drawn from observation and experience; which facts, collected and multiplied to a certain degree, lead to conclusions that are equivalent to the most demonstrable truths.