476 



EXPERIMENTAL PHARMACOLOGY 



every room in the building. It is important to consider this 

 point in the construction of new laboratories. 



Equipment. The following list of tools and supplies is by 

 no means complete and is intended merely to serve as a 

 guide for those who may care to prepare themselves to do 

 a certain amount of shop work but who may have had no 

 previous training in this field. 



The author has attempted to arrange the tools, etc., as 

 nearly as possible in the direct order of their usefulness 

 in the laboratory and with reference to the amount of money 



From air tank 



Extra holes 

 for pins 



Worm gear 



Trip pins 



Lever gate valve 



Cone pulley 



Round belt 



- Flange 



Fig. 365. Special form of interrupting valve using cone pulleys, worm gears, and 

 having adjustable trip pins to open the lever gate valve. This valve can be used where 

 compressed air is already furnished to the laboratory from the power house. Air thus 

 supplied is often under high pressure (35 to 70 pounds or more). There are special 

 reducing and regulating valves on the market to reduce this pressure as it is received 

 into a special tank in the laboratory. One can use a .pressure of 35 pounds for artificial 

 -esiiiration if he has a suitable interrupting valve, one which onens only a little ways 

 and for a very brief period. Excessive quantities of air are usually passed to the animal 

 but most of this escapes at once through the side tube of the tracheal cannula. This 

 xlionld always be u'idc open before artificial respiration is started. The instructor should 

 fully impress this on the students. 



which the department may be able to spend for the shop 

 equipment. Thus the list begins with those cheap hand 

 tools which are most likely to be of the greatest service in 

 laboratories where the funds are limited. As the number 

 of tools multiplies in the list the degree of usefulness is 



