CHAP. XXVIII.] 



THE H^EMODROMOMETER. 



365 



instrument in using it, the glass tube is attached to a board, to 

 which is fixed a scale marked in metal. 



In order, then, to use the instrument, a large artery is freely ex- 

 posed for not less than three inches ; and, after due precaution has 

 been taken to counteract hemorrhage, it is divided by cutting out a 

 piece ; the conical pipes (k, k') are then fixed into the open ends 







Fig. 202. 



of the artery, one being directed towards the heart, the other 

 towards the capillaries. They must be fixed far enough apart 

 to admit of the introduction of the horizontal tube (A) between 

 them, without altering the usual direction of the arterial stream. 



