Carpenter's principles of human physiology . from 1 to 2 in thesecond stimulation, the effect of which is represented by b. There is a latent stage varying from2-5 to 0-l second in both. 240. The distension of the Fro. 133. Arteries that is consequent uponthe intermittent injection of bloodinto their trunks gives rise tothe pulsation which is perceptibleto the touch in all but the smallestarteries, and which is visible tothe eye when they are exposed. It would seem to the touch, as if The dark line shows the period during which a powerful this wprp phipflv pflfor-rorl V,™ or, e,ec,trical stimu
Carpenter's principles of human physiology . from 1 to 2 in thesecond stimulation, the effect of which is represented by b. There is a latent stage varying from2-5 to 0-l second in both. 240. The distension of the Fro. 133. Arteries that is consequent uponthe intermittent injection of bloodinto their trunks gives rise tothe pulsation which is perceptibleto the touch in all but the smallestarteries, and which is visible tothe eye when they are exposed. It would seem to the touch, as if The dark line shows the period during which a powerful this wprp phipflv pflfor-rorl V,™ or, e,ec,trical stimulus was simultaneously applied 10 the svm- UllS were CHieny ettected by an pathetic and to the chorda tympani nerve. It is seen that increase 01 diameter, and the ex- the sympathetic first responds to the stimulus as in Fig. ~~~;™,-,~i.„ ~f \T ll /ll tt-. 131> overcoming the chorda, but the chorda subsequently perirnents of Volkmann (Ha- exerts its full action. modynamik) led him to believe that the transverse dilatation is greater. 312 OF THE CIRCULATION OF THE BLOOD. than the longitudinal; but these experiments were made under conditionsso different from those of the living artery, that but little weight canbe attached to them. It is to be remembered, however, that every increasein length augments the capacity in only a simple ratio; thus a tube of 21inches in length will only contain one-twentieth more than a tube of 20 incheslong, of the same diameter. On the other hand, every increase in diameteraugments the capacity of the tube in the ratio of the square of that increase;thus the capacity of a tube of 21 lines in diameter will be to that of a tube of20 lines, as 441 : 400, or one-tenth more. Consequently, supposing the increaseof capacity to take place equally in both directions, the increase in longitu-dinal dimension will be far more apparent than the transverse total increase of capacity was estimated by Flourens, from experimentsupon the carot
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectphysiology, bookyear1
