A course of elementary practical physiology and histology / by M. Foster and J.N. Langley.

  • Michael Foster
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: A course of elementary practical physiology and histology / by M. Foster and J.N. Langley. Source: Wellcome Collection.

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    water. Take a series of watch-glasses and into each put 1 c.c. of the rfo normal acid as follows:— 9 1. 0*9 c.c. TJT normal tartaric acid + 0*1 c.c. Na2S04 sol. 2. 0-8c.c. „ » n +0-2 c.c. „ 3. 07 c.c. „ >» 11 +0*3 c.c. „ ,, and so on. Add to each watch-glass 0-1 c.c. of freshly drawn blood. After stirring determine by litmus paper which is neutralised by the blood. The amount of acid which neutralises 0*1 c.c. of the blood is thus found, and since the amount of NaHO which will neutralise this acid is known, the alkalinity of 100 c.c. of blood can be expressed as equivalent to a definite amount of sodium hydrate. The alkalinity of normal human blood is equivalent to -2 to '3 gr. per cent, of NaHO. 8. Determination of the specific gravity of blood. A series of solutions of glycerine and water of specific gravity varying between 1035 and 1068 are prepared. Pour a little of one of them, of sp. gr. 1050 for example, into a narrow but deep glass vessel. Prick the finger and suck up a drop of blood into a fine glass pipette, the point of which is bent at right angles to the main tube. Gently blow the drop of blood out of the pipette so that it issues horizontally into the middle of the glycerine solution. If the blood immediately sinks, take a glycerine solution of higher sp. gr., if it rises, one of lower sp. gr. and make another observation with another drop of blood. After a few trials a solution will be found in which the blood neither sinks nor rises immediately. The blood is of the same sp. gr., as this solution. 9. Enumeration of the red corpuscles. Count the number of red corpuscles with Thoma's hemacytometer in the following manner. See that the counting cell and the pipette are clean and have ready a large coverslip and a watch-glass containing the diluting fluid. This may be sodium sulphate solution of sp. gr. 1025, sodium chloride -8 % solution, or Hayem's fluid, which consists of 1 part of sodic chloride, 5 parts of sodic sulphate, 5 parts of corrosive sublimate in 200 parts of water. Prick the finger and when a sufficiently large drop of blood
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