4:0 LABORATORY EXERCISES. 



b. Place in another test-tube the same 



quantity of minced egg and water 

 as in tube No. i ; add a little di- 

 lute hydrochloric acid. Label Test 

 No. 2, minced egg + water + hydro- 

 chloric acid. 



c. Into a third tube put some minced egg 



and water, and add a small amount 

 of pepsin. Label Test No. 3, 

 minced egg -f water + pepsin. 



d. Place some of the minced egg into a 



fourth tube and add all three in- 

 gredients of gastric juice, namely, 

 water, a little hydrochloric acid, 

 and pepsin. Label Test No. 4, 

 minced egg + water + hydrochloric 

 acid-f- pepsin. 



e. Put a lump of the hard-boiled egg in a 



fifth test-tube; add water, hydro- 

 chloric acid, and pepsin, as in Test 

 No. 4. Label Test No. 5, lump of 

 egg + water + hydrochloric acid-H 

 pepsin. 



/. Put all five tubes in a warm place (98 

 F.) and shake them at frequent in- 

 tervals. Examine them at the end 

 of a few hours and at the end of a 

 day or two. 

 2. Results and conclusions. 



a. Compare tests i, 2, 3, and 4. 



(i) In which tube has the egg been 

 liquefied or digested? 



