14 PHYSIOLOGY FOR THE LABORATORY. 



Bunsen burner until it turns white. Be very careful 

 neither to lose any of it nor to burn it too long. 



c. What happens ? 



d. Touch it ; what happens ? 



e. What is its chief structure and general appearance ? 

 /. What have you left? 



g. Weigh it. 



h. Calculate the amount of mineral matter in the bone. 

 i. What has become^ of the animal matter? 

 j. Calculate the amount of animal matter in bone. 

 k. Place the burned bone in dilute, ten per cent, hydro- 

 chloric acid. 



I. What happens ? Why ? 



m. Add ammonium hydrate (ammonia) in excess. 

 n. What happens ? Why ? 



The mineral matter consists of eighty-three per cent of 

 calcium phosphate, Ca 3 (PO 4 ) 2 , thirteen per cent of calcium 

 carbonate, CaCo 3 , and of other salts. The animal matter 

 consists mainly of an albuminoid, ossein, or collagen, which 

 may be converted by boiling with water into gelatin. 



II. THE ANIMAL MATTEK. 



a. Place a. long, slender bone, such as a rib-bone, in 

 dilute, ten per cent, hydrochloric acid in a tall, narrow 

 jar, and leave it for a day or longer according to the size 

 of the bone. Dilute nitric acid or vinegar may also be 

 used. 



b. Touch it ; can you bend it ? 



c. What are its characteristics now? 



d. What has taken place? 



e. What have you left ? 



