384 APPENDIX. 



Any other form of pump can be used. 



At S fJ S a ', S v ' are placed vertically above one another 

 either the usual sphygmograph levers or light levers 

 such as are used to take tracings of the movements 

 of the frog's heart (cp. p. 349). The tubing can 

 be supported on pieces of lead bent to fit its course 

 and fastened to a stand. Each of the tubes A and 

 F communicates with a mercurial manometer. 



The rest of the scheme requires no explanation further 

 than that which is given in the text. 



MINOR ARTERIAL SCHEME. 



This consists of an india-rubber bag like that used in 

 the major arterial scheme. By means of a three-way 

 tube, the end of this, towards which the valves open, 

 is connected both with a piece of glass tubing about 

 a yard and a half in length, and with a piece of 

 india-rubber tubing of similar length and bore. 



There are clamps upon the long india-rubber tube close 

 to its junction with the three-way tube and upon 

 the small piece of india-rubber which connects the 

 three-way tube with the glass tube, so that the flow 

 of water may be through either the glass or the 

 india-rubber tube. 



A small piece of india-rubber tubing is also placed on 

 the end of the glass tube, into which a tube finely 

 drawn out can be inserted. 



To DESTROY THE BRAIN OF A FROG. 



Place the frog under a small bell-jar with a sponge 

 moistened with ether; when the animal is motion- 



