The Croonian lecture on muscular motion / by George Fordyce.

  • Fordyce, George, 1736-1802.
Date:
[1788]
Catalogue details

Licence: Public Domain Mark

Credit: The Croonian lecture on muscular motion / by George Fordyce. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    5/16 (page 5)
    mention the increafe at times of the circulation, and all the motions of the fluids without the leafl; new motion in the fur- rounding bodies, or interference, or even knowledge of the mind. This motion mufl: therefore be original, and not com- municated. In communicated motion, if one body be at refl:, and a mo- tion be communicated to it by another, the power of the whole motion fhall not be greater than that in the communicating body at the time of the communication. If 1 take out the heart of an animal, cut off the auricles, it will in many cafes continue to contrafl and dilate for fome time. If it be left to come to refl;, and if foon after a needle be introducedJnto the ventricle, placed tranfverfely, and if the interior furface of the ventricle be pricked gently by the needle, the ventricle will contradt with fuch power as to force the needle deep Into it: in this cafe, the force of the contradllon of the ventricle is much greater than the power with which it .was pricked by the needle i this contradlion was therefore not communicated to it by the moving needle, but was generated, and therefore an original motion. In all communicated motion, by which two bodies at a dif- tance are brought near to one another, there mufl fubfifl fome other matter, by which they may be drawn, or forced, nearer to one another; but in original motion, it is not at all neceflary that any other matter fliould exifl at 'all. Two particles, placed at as great a diflancefrom one another as the fun is from the earth, as has been already obferved, although at perfedt refl, would begin to move nearer^one another, by the attradllon of gravitation, if all other matter whatever were annihilated. Mofl authors who have treated on mufcular motion have fuppofed, that it was a communicated motion j and that it was B produced