310 LABOR A TOR Y G UIDE IN PHYSIOLOG Y. 



remove the influence of the nervous system. Curara 

 also spelled curare, curari, urari, and woorara, woorari, 

 wourali, etc., an arrow poison used by the South Amer- 

 ican aborigines, is the means usually employed to accom- 

 plish the end desired. The way in which curare exerts its 

 influence, is made the subject of study in another place. 

 Make a 1% solution by pulverizing 1 gramme of commer- 

 cial curare, and dissolve it in 100 c. c. of distilled water. 

 It need not be filtered unless intended for use with a 

 hypodermic syringe. If kept in a ground glass stoppered 

 bottle, in a cool place, it will retain its efficiency for 

 months. 



The most convenient method of curarizing a frog is to 

 inject with a narrow pointed pipette, 1-3 drops of the 

 solution, through a minute ventral cutaneous incision. 



The drug will begin to take effect in a few minutes. 

 The maximum effect may be delayed some time. 



6. To prepare the kymograph for work. 



Remove the cylinder, stretch a sheet of the prepared 

 glazed paper tightly upon the surface, place it upon such 

 a stand as the one shown in Fig. 54; set the drum to 



FIG. 54. 

 FIG. 54. Drum support for use in smoking the kymograph drums. 



rotating and bring the triple gas flame under the drum. In 

 a few moments it will be evenly covered with a film of 



