pulse wave (pulswav)

The wave of raised tension and arterial expansion which starts from the aorta with each ventricular systole, and travels to the capillaries. Its velocity varies greatly, but in most cases lies between 4 and 12 meters per second. - Fundamental or primary pulse-wave, the wave resulting from the primary or ventricular impulse; the wave indicated by the initial with steam-pa ages; c is a spherical valve which excludes the steam from one chamber while permitting it to flow into the other. Steam enters at s; d is an induction pa age for water; e and e ' are vulcanized rubber valves; f and f ', valve-seats; h, the delivery - pa age, shown (with other parts) in dotted outline; g and g ', eduction valves for water; i and i ', valve-guards; j, air-chamber; kand k ', bonnets covering openings whereby the IMG:content-1295.png:[blocks in formation] valves may be reached for adjustment or repair; I and l ', rods which hold the induction-valves and their attachments in place; n and n ', bra socket-headed bolts which secure the valves g and g ' and their attachments in their places. Into the neck of each of the chambers a and a ' is screwed a small inlet air-valve (not shown). A similar valve is fitted to the chamber j. Steam entering chamber a expels its contents, and then, condensing, forms a partial vacuum. The valve then closes the opening into that chamber, and admits steam into the other. Water then rises to fill the vacuous chamber; also a little air enters through the minute air valve in the neck. By this time the contents of the other chamber are expelled, the steam condenses therein, and other events follow as described for the first chamber. The small quantity of air admitted, being heavier than steam, forms a film over the upper surface of the water, and, being a non-conductor of heat, prevents wasteful condensation of steam, which would otherwise arise from the direct contact of the steain with the water. The machine de rives its name from the pulsatory action of the steam ejected, and the analogy of its form, with its interior valves, to the construction of the heart. Also called aqua meter. puls us (pul's us), n. [L.: see pulse1.] The pulse. - Pulsus alter nans, a pulse in which alternate beats are strong and weak. -- Pulsus bigeminus, a pulse made up of cycles consisting of two beats followed by a pause.Pulsus celer, a quick pulse. See pulse. - Pulsus dicrotus, a dicrotic pulse. See pulse. - Pulsus differ ens, a pulse unequal in strength, or di imilar in form in the two radials. Pulsus durus, a hard pulse. See pulse. - Pulsus filiform is, a filiform pulse. See pulse. -Pulsus hyperdicrotus, a hyper dicrotic pulse. See pulse. - Pulsus inter cur rens, a pulse in which there is an extra beat in tercalated in a normal series. - Pulsus inter mittens, an intermittent pulse. See pulse. - Pulsus magnus, a large pulse. See pulse. - Pulsus moll is, a soft pulse. See pulse. - Pulsus monocrotus, a monocrotic pulse. - Pulsus myurus, a pulse which becomes feebler and then stronger in alternate series. - Pulsus paradox us, a pulse pulu (poʻlö), n. [Hawaiian.] A fine silky yel lowish fiber obtained in the Hawaiian Islands from tree-ferns of the genus Cibotium, the bases of whose leafstalks it densely covers. It is exported in considerable quantity, chiefly to San Francisco, for use in stuffing mattre es, etc. A species of the genus, C. Barometz, of tropical Asia and the Malayan islands, yields (as do also species of Dicks on i a ) a like product, used for the same purpose, and also employed in surgery as a mechanical styptic. pulv. An abbreviation of Latin pulvis, powder: used in medical prescriptions.