CH. XXI.] 



THE KYMOGRAPH. 



289 



is exhibited on the tracing, with small waves as before corre- 

 sponding to heart-beats, and larger waves to respiration, only 



Fig. 277. Normal tracing, somewhat magnified, of arterial pressure in the rabbit obtained 

 with the mercurial kymograph. The smaller undulations correspond with the heart- 

 beats, the larger curves with the respiratory movements. (Burdon-Sanderson.) 



the respiratory rise in pressure now accompanies expiration 

 (see p. 277). 



The capillary pressure is estimated by the amount of pressure 





Fig. 278. A form of Pick's Spring Kymograph, a, tube to be connected with artery ; r, 

 hollow spring, the movement of which moves 6, the writing lever ; e, screw to regulate 

 height of 6 ; d, outaide protective spring ; g, screw to fix on the upright of the support. 



necessary to blanch the skin ; this has been done in animals and 

 men (v. Kries, Roy and Brown). 



Other manometers are often employed instead of the mercurial 

 one. Kick's is one of these. The blood-vessel is connected as before 



K.P. u 



