DIGESTION OF FAT8. 43 



slide, cover with a cover-glass, and 

 examine with a compound micro- 

 scope. 



(1) What is the appearance of the 



oil droplets? 



(2) Compare this appearance with 



that seen in milk. (See ex- 

 periment J5 E.) 



2. In a test-tube shake some olive -oil with a 



mixture of white of egg (albumin) and 

 water. 



a. What is the appearance of the mix- 



ture? 



b. Examine a drop under the compound 



microscope as directed above. 



3. Shake up a few drops of the olive-oil with 



water in a third test-tube, and let tube 

 stand for a time. 



a. Compare the mixtt-^e of oil and water 



with the '.fixtures formed in i and 

 2 above. 



b. What differences do you notice in the 



tubes ? 



4. Summary. 



a. Define an emulsion. 



b. State two ways in which an emulsion 



can be made. 

 C. Saponification of fats. 



i. Put a little lard or olive-oil in a test-tube, 

 add caustic soda, and boil, 

 a. What is the appearance of the mix- 

 ture? 



