A text-book of physiology . s filled above the mercury with some innocuous fluid, as is alsothe tube connecting the manometer with the artery. Using suchan instrument we should observe very much the same facts as inthe more simple experiment. Immediately that communication is established between theinterior of the artery and the manometer, blood rushes from theformer into the latter, driving some of the mercury from the de-scending limb, m, into the ascending limb, mf, and thus causingthe level of the mercury in the ascending limb to rise rise is marked by jerks corresponding with
A text-book of physiology . s filled above the mercury with some innocuous fluid, as is alsothe tube connecting the manometer with the artery. Using suchan instrument we should observe very much the same facts as inthe more simple experiment. Immediately that communication is established between theinterior of the artery and the manometer, blood rushes from theformer into the latter, driving some of the mercury from the de-scending limb, m, into the ascending limb, mf, and thus causingthe level of the mercury in the ascending limb to rise rise is marked by jerks corresponding with the heart reached a certain level, the mercury ceases to rise anymore. It does not, however, remain absolutely at rest, but under-goes oscillations; it keeps rising and falling. Each rise, which isvery slight compared with the total height to which the mercuryhas risen, has the same rhythm as the systole of the , each fall corresponds with the diastole. Chap, iv.] THE VASCULAR MECHANISM. 207. Fig. 26 208 BLOOD PRESSUEE. [Book j. Fig. 26. Apparatus for investigating Blood Pressure. At the upper right-hand corner is seen, on an enlarged scale, the carotid artery,clamped by the forceps bd, with the vagus nerve v lying by its side. The arteryhas been ligatured at /, and the glass cannula c has been introduced into the arterybetween the ligature / and the forceps bd, and secured in position by the ligature shrunken artery on the distal side of the cannula is seen at ca. is a box containing a bottle holding a saturated solution of sodium car-bonate, or of sodium bicarbonate, or a mixture of the two, and capable of beingraised or lowered at pleasure. The solution flows by the tube regulated by theclamp c into the tube t. A syringe, with a stopcock, may be substituted for thebottle, and attached at c. This, indeed, is in many respects a more convenient tube t is connected with the leaden tube t, and the stopcock c with the mano-
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Keywords: ., bookautho, bookcentury1800, bookdecade1890, booksubjectphysiology
