LABORATORY EXERCISES 405 



CHAPTER VI 



Page 90. The body cavity, its divisions and contained organs, should 

 be made plain by use of a manikin. 



If some animal such as cat, rabbit, white rat, or the like can be dissected, 

 the entire teaching of the body cavity and contained organs can be very 

 easily made clear. 



Page 94. Coagulate some white of egg in boiling water in a beaker. 

 Note that water alone will not dissolve such proteid. Put a piece of egg 

 as large as the end of one's little finger (mincing it first) into a test tube 

 half full of artificial gastric juice (see formula). Stand the test tube in a 

 beaker of water kept at about body temperature (98) and note that the 

 egg slowly dissolves. When it has gone into solution, add copper sulfate 

 and caustic potash ; a rose-red color instead of violet shows that the pro- 

 teid has been changed into peptone. 



Page 94. A solution of rennet can be obtained from any druggist, 

 and its action on milk shown by merely adding a little to a tube of warm 

 milk and allowing it to stand for about | hour. 



CHAPTER VII 



Page 99. A very useful demonstration of the intestine with arteries 

 and veins injected, and the whole made translucent, can be obtained from 

 the W. H. Welsh Manufacturing Company, 1516 Orleans St., Chicago. 



Page 100. The teacher should demonstrate all the organs described 

 in this chapter, as well as details like the mesentery, gall bladder, etc., 

 by use of a manikin of the human body, or by the dissection of some small 

 mammal. Even a fish shows much of interest in this connection, but 

 has no diaphragm and is unlike the human in numerous ways. 



Page 101. The bile duct, gall bladder, and liver lobes are very easily 

 dissected in the dog-fish. 



Page 103. Artificial pancreatic juice should be placed in a test tube 

 with coagulated white of egg, kept at body temperature, and the test for 

 peptones made. Starch should be treated in the same way, and after its 

 digestion, tests made for sugar. 



To show action of pancreatic secretion on fats it is best to imitate the 

 conditions present in the intestine by mixing with the artificial pancreatic 

 juice a little white of egg, as other things besides fat are always present. 

 Pour into such a mixture some olive oil and shake vigorously. The emul- 

 sion thus formed will not separate as does a mixture of oil and water, 



sion 



