Volume 1

A text-book of human physiology : including histology and microscopical anatomy with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition with additions by William Stirling.

Landois, L. (Leonard), 1837-1902. Lehrbuch der Physiologie des Menschen. English

Date:: 1891

Credit: A text-book of human physiology : including histology and microscopical anatomy with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition with additions by William Stirling. Source: Wellcome Collection.

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$temperature and the addition of an alkali favour the formation of the acid {JH, Zuntz). The alkaline reaction of blood is diminished : (a) by gi'eat muscular exertion owing to the formation of a large amount of acid in the muscles ; {ß) during coagulation ; (7) in old blood, or blood dissolved by water from old blood-stains, sucli blood being usually acid ; fresh cruoi has a stronger alkaline reaction than serum ; (8) after the prolonged use of soda the alkalmity is increased after the use of acids it is decreased. In women and children the alkalescence is less than in man, and it is less in lying-in women than in pregnant women {Peiper). Methods -Owing to the colour of the blood we cannot employ ordinary litmus paper to test its reaction. One of the following methods may be used Moisten a stnp of £azed red litmus paper with solution of common salt, and allow a drop of blood to fa 1 on the papei , then rapidly wipe it otr before its colouring matter has time to penetrate and tinge the paper (Zuntz). (2) Liebreich used thin plates of plaster-of-Paris of a perfectly neutral reaction These are dried, and afterwards moistened with a neutral solution ot litmus. _A\hen a drop of blood is placed upon the porous plate, the fluid part of the blood passes into it, the cor- puscles are then washed off with water, and the altered colour of the litmus-stamed slab is apparent. [(3) Schäfer uses dry faintly-reddened glazed litmus paper, and on it is placed a d??p of blood, Avhich is wiped off- after a few seconds. The place where the blood rested is indicated by a blue patch upon a red or violet ground.] Estimation of the AlkaliW.-A very dilute solution of tartaric acid (1 cubic cen imetre combines with S'l milligrams of soda, i.e., 1 Htre of water contains 7-5 grams 0 ^Tsta hs^d tartaric acid) is added to blood until a blue litmus paper is turned red (by Zuntz s rr ethod) 100 grams of rabbit's blood have an alkalinity corresponding to 150 milligrams of so^a the blood of Carnivora to about 180 milligrams {Lassar), while 100 c.c. of normal human blood have an alkalinity equal to 260-300 milligrams of soda {v. JakscJi). ■, ,, . ^ Tl ffohowinnietho can be used°with a few drops of blood :-To neutralise the blood, tar- taric acid in tlfe above concentration is used. Prepare the follo^ylng mixtures by mixing the tartaric acid solution with a concentrated neutral solution of sodic sulphate, and hen adding sodic sulphate until the mixture is completely saturated. I 10 P^^ts of solution of taitarn acid to 100 parts of concentrated sodic sulphate solution ; II., 20 parts tartaric acid solution to 90 sodic sulphate solution ; III. contains these substances m the pr^^ ^qVto 2o'. and 40 to 70 • Y 50 to 60 ; YL, 60 to 50 ; YIL, 70 to 40 ; YIIL, 80 to 30 ; IX., 90 to 20 , and X., 100 to 10.' Excess of sodic sulphate is present in all the flasks. A known volume of the blood to be investigated is mixed with an equal volume of each of thf mi^tres, in a small tube, which is made by drawing out a glass tube 1 mill^^^^^^^^ diameter to a fine point. To calibrate this tube, suck up water, say, to the height ot 8 mm., tke a mark on tL tube with a fine file, then suck up the water until -/^^S'^ snonds with the mark. Again mark the upper limit of the water, lo test the blood, suck a dCp of the mixture I. up to the level of the first mark on the glass pipette, and after wiping its poin su?k up an eqial quantity of blood. Again clean the point of the pipette, and blow oTten^rhito^i watch-glass ; then mix, and test the reaction with sensitive -olet^co oured litmus paper. Proceed in the same way with the several mixtures II. to X., unt 1 the aSne Son disappears or the acid appears. The narrow strips of litmus paper are dipped ii^to Lh of th^^^^^^ the corpuscles remain in the wetted part of the paper, while the Slid peimeates^^ and shows the reaction. As a rule, the degree of alkalinity m human Wood^of adul s c^^^^^ to YL, and in children to lY. Human blood can be sucked dii-ect^^^ from a small wound made by a needle, either by attaching an elastic tube or a small hypodeimic 'TSlZl^Z Suni?y is increased during persistent vomiting, and decreased in pi.- nounced aLmia cachexia, uraemia, rheumatism, high fever, diabetes, m poisoning with CO Segeneratioir^^^^ cholera. [Immediately before death by cholera it may be acid {Gantani).] (3) Odour.—Blood emits a peculiar odour, the halitus sanguinis, which differs in animals and man. It depends upon the presence of volatile fatty acids. If concentrated sulphuric acid [H vo s l Kdded to blood, whereby the volatile fatty acids are set free from their combinations with alkalies' the characteristic odour, somewhat similar to that of butyric acid, becomes much more perceptible. (4) Taste.—Blood has a saline taste, depending upon the salts dissolved in the fluid of the blood. . . . .^^^ (5) Specific Gravity.—The specific gravity is 1056-1059 m man, 1051-1055 in woman; in children less. The specific gravity of the blood-corpuscles is 1105, that of the plasma 1027. Hence the corpuscles tend to sink.$