A MANUAL OF PHYSIOLOGY 



The result is the percentage actually present of the average propor- 

 tion of haemoglobin in the blood of healthy adult males. Healthy 

 women give an average of only 89 per cent., and healthy children 

 an average of only 87 per cent., of the proportion in men. The 

 liquid in A is a i per cent, solution of blood containing the average 

 percentage of haemoglobin found in the blood of healthy adult males, 

 and having an oxygen capacity of 18*5 per cent. i.e., 100 c.c. of 

 the blood with which the standard was made would take up jn 

 combination from air 18*5 c.c. of oxygen. The solution in A has 



been saturated with carbonic 

 oxide. 



This method is probably 

 more accurate than any other 

 used in clinical work, the 

 error, in the hands of an ex- 

 perienced observer, not ex- 

 ceeding i per cent. 



(b) By Fleischl's HcBmometev 

 (Fig. 1 8) .Fill with distilled 

 water that compartment a' of 

 the small cylinder (above the 

 stage) which is over the tinted 

 wedge. Put a little distilled 

 water into the other compart- 

 ment a. Now prick the finger 

 and fill one of the small 

 .capillary tubes with blood. 

 See that none of the blood is 

 smeared on the outside of the 

 tube. Then wash all the blood 

 into the water in compartment 

 a, and fill it to the brim with 

 distilled water. By means of 

 the milled head T move the 

 tinted wedge K till the depth 

 FIG. 19. DIAGRAM OF PRIMITIVE VERTE- of colour is the same in the 

 BRATE HEART, COMBINING FEATURES two compartments. The per- 

 FOUND IN THE EEL, DOGFISH, AND FROG centage of the normal quantity 



of haemoglobin is given by 

 the graduated scale P. For 

 example, if the reading is 90, 

 the blood contains 90 per cent, 

 of the normal amount ; if 100, 

 it contains the normal quan- 

 tity. The observations should 

 be made in a dark room, 



the white surface S, arranged below the compartments a and a', 

 being illuminated by a lamp. Or the instrument may be placed in a 

 small box, lighted by a candle. It is best that each result should be 

 the mean of two readings, one just too large and the other just too 

 small. In any case the instrument does not give readings accurate 

 to less than 5 per cent. 



(c) Hoppe-Seyler's Method. Two parallel-sided glass troughs are 

 used. In one is put a standard solution of oxyhaemoglobin of 

 known strength, in the other a measured quantity of the blood to be 

 tested. The latter is diluted with water until its tint appears the 



(FLACK, AFTER KEITH). 



a, Sinus venosus ; b, auricular canal ; 

 c, auricle ; d, ventricle ; e, bulbus cordis ; 

 /, aorta ; i-i, sino -auricular junction and 

 venous valves ; 2-2, junction of canal and 

 auricle ; 3-3, annular part of auricle; 5, bulbo- 

 ventricular junction. 



