Physiology : preliminary course lectures / James T. Whittaker.

  • Whittaker, James T. (James Thomas), 1843-1900.
Date:
1879
Catalogue details

Licence: Public Domain Mark

Credit: Physiology : preliminary course lectures / James T. Whittaker. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    character of the impressions determines the character of the mind. In other words:— •'L'instruction fait tout; et les mains de nos peres Grave en nos faible cceurs ces premieres characteres Que l'example et le temps nous viennent retracer Et que peut-etre en nous Dieu seul peut effacer. Voltaire. (Instruction does all ; our father's hands Engrave in our hearts indelible bands, Which time and example only retrace And which God [death] alone may ever efface.) Hate of Conduction. Although we are ignorant of the ultimate essence of nerve force we are by no means entirely unacquainted with its properties and effects. We have in the first place some quite definite information as to the velocity or rapidity with which it travels. When this question first excited the attention of physiologists, it was considered a subject beyond the possibilities of human comprehension. Haller thought that it would be impossible to measure the rate of conduction of nerve force because there was not sufficient distance for estimate as in the case of light. But as Goethe has said one must continue to believe the inconceivable to be conceivable, else there will be no discovery. Continued investigation has at last been rewarded with positive results so that we possess now tolerably accurate data regarding the velocity of nerve force. By attaching two levers to two different parts of a muscle and causing the muscle to contract by stimulating successively two different parts of the trunk of the nerve terminating in the muscle, Marey wras able to determine that the response of the muscle was quicker to the irritation nearer the muscle. The interval which lapsed between response to stimulus at different points along the nerve corresponds to the rate of conduction between the points. The distance between these points