STUDY OF PEEP BLOOD. 51 



c. Gently shake the bottle. Describe 



the consistency of the clot. 



d. What is its color? Is the whole mass 



of the same color? 



4. Determine the composition of the blood- 

 serum by the following experiments : 



a. Pour a small portion of the serum 



into a test-tube and heat gradually 

 over an alcohol lamp ; what change 

 takes place? What kind of nutri- 

 ent do you, therefore, conclude to 

 be present? 



b. Dip a piece of unglazed paper into the 



blood-serum and allow the paper 

 to dry. How is the paper affected ? 

 What is the second food-stuff 

 found in serum? 



c. Test a little of the serum with iodine. 



What is the result? Why ought 

 this result to have been expected? 



d. Pour into another portion of the se- 



rum some Fehling's solution and 

 boil. What is the result? Did 

 you expect this result? Can you 

 suggest any possible explanation 

 of this result? 



e. Put a few drops of the serum on a 



piece of platinum foil and heat as 

 hot as you can in a gas flame. De- 

 scribe the various changes that take 

 place and explain each. What 

 kind of material is left after the 





