APPENDIX 



219 



Oliver, is a ready way of determining the total number of corpuscles. It is, 

 however, not possible to determine the relative proportion of red and white 

 corpuscles by this means. 



The linger is pricked, and the blood allowed to flow into the small 

 capillary pipette (fig. 65, a) until it is full. This is washed out by the 

 dropping tube b into a graduated flattened test-tube, c, with Hayem's fluid. 1 

 The graduations of the tube are so adjusted that with normal blood con- 

 taining 5,000,000 coloured corpuscles per cubic millimetre, the light of a 

 small wax candle placed at a distance of 9 feet from the eye in a dark room 

 is just transmitted as a fine bright line when looked at through the tube held 

 edgeways between the fingers (d) and filled up to the 100 mark of the gradua- 

 tion. If the number of corpuscles is less than normal, less of the diluting 

 solution is required for the light to be transmitted ; if above the normal, more 

 of the Hayem's fluid must be added. The tube is graduated, so as to indicate 

 in percentages the decrease or increase of corpuscles per cubic millimetre as 

 compared with the normal standard of 100 per cent. 



HaiMOGLOBINOMETERS 



Gowers's Hsemoglobinoineter. The apparatus consists of two glass tubes, 

 C and D, of the same size. D contains glycerin jelly tinted with carmine to 

 a standard colour viz., that of normal blood diluted 100 times with distilled 

 water. The finger is pricked and 20 cubic millimetres of blood are measured 



FIG. 66. HaRmoglobinometer of Sir W. Gowers. 



out by the capillary pipette, B. This is blown out into the tube C, and diluted 

 with distilled water, added drop by drop from the pipette stopper of the 

 bottle, A, until the tint of the diluted blood reaches the standard colour. The 

 tube C is graduated into 100 parts. If the tint of the diluted blood is the 



1 Sodium sulphate 5 grammes, sodium 

 0-5 grm., distilled water 200 c.c. 



chloride 1 grm., mercuric chloride 



