DE. A. GAMGEE ON THE ACTION OE NITEITES ON BLOOD. 
613 
In my experiments on the gases of the blood, I have used Sprengel’s mercurial 
aspirator for exhausting my apparatus and obtaining the gases of blood. The results 
which I have obtained with this instrument have been remarkably satisfactory, and of 
such a nature as to lead me to think that it may supersede the very expensive and more 
complicated mercurial blood-pump of Geissler. In the annexed diagram I have exhi- 
bited the apparatus which I employed. 
J hik exhibits a section of a wooden stand which is 4 feet high, and which supports 
three tin boxes, x, y, and z. The box x is intended to be used as a water-bath, and 
is heated by a gas-burner placed below it. y and z are tin boxes to be filled with cold 
water. 
a exhibits the glass bottle into which is received the blood to be exhausted, and of 
which a larger diagram is given below. The neck a of this bottle is very accurately 
ground, and into it fits the ground tube deb, which dips to the bottom of the bottle, 
and which is bent at c. The bottle has an exit-tube, f. 
The open end of b e d is closed by means of a narrow tube of black india-rubber, which 
is wired (after having been smeared on the inside with melted india-rubber) and furnished 
with a very perfect steel clip. Besides having the tube deb very perfectly ground, the 
tightness of the apparatus is further secured by pouring melted shellac into the hollow 
