292 



EXPERIMENTAL PHARMACOLOGY 



(Fig. 258). With a scalpel cut close to the bone and dis- 

 sect loose the right temporal muscle. Reflect this upward 

 and hold it up with forceps. Take a trephine instrument 



Fig. 258. Method of making the first incision before trephining the skull. The 

 longitudinal (mesial) edge of the opening is cut with a scalpel. The triangular piece 

 of skin and fascia is then lifted with forceps and cut awajj with heavy (6 inch) tinner's 

 snips. 



Fig. 259. The trephine opening is made about one-half to three-fourths of an inch 

 outward from the median line to avoid the great longitudinal sinus. 



(Fig. 100) and make an opening in the skull (Fig. 259). 

 Be careful to aroid the lout/it x.dinal xhtu* tlie opening 

 should be one-It alf to three-fourths of an inch away from 



