RESPIRATION 



405 



that the Gowers haemoglobinometer could be made a very exact instru- 

 ment for determining the oxygen capacity of blood, and could also be 

 improved in other respects. I introduced the necessary improvements in 

 1901.^ For the picrocarmine solution there is substituted a i per cent 

 solution of blood with an oxygen capacity of 18.5 cc. per 100 cc. of blood, 

 since the average of a number of normal men showed that this is the 

 average oxygen capacity for men. To make this solution keep its coloring 



Figure 102. 

 Gowers-Haldane Haemoglobinometer 

 A — Glass tube containing blood solution of standard tint. 

 B — Graduated tube. 

 C — Rubber stand for tubes A and B. 

 D — Capillary pipette and suction tube ; wires for cleaning 



the pipette are supplied. 

 E — Bottle with pipette stopper. 

 F — Glass tube holding 6 lancets. 

 G — Tube and cap for fixing over ordinary gas burners. 



power it is saturated with CO, and sealed up with only CO, and no oxy- 

 gen, in the empty space above the blood solution. Hoppe Seyler had 

 already found that a strong solution of CO haemoglobin retains its 

 coloring power. This is also true for a dilute solution ; and the standard 

 haemoglobinometer tubes filled and sealed twenty years ago have re- 

 mained absolutely unaltered in color. 



" Haldane, Journ. of Physiol., XXVI, p. 497, 1901. The instrument is made 

 by Hawksley, Wigmore Street, London, W. 



