384 A MANUAL OF PHYSIOLOGY 



before and after boiling with one-twentieth of its volume of hydro* 

 chloric acid. 



(d] Estimate in the same way the amount (as glucose) of the invert 

 sugar in the standard solution of cane-sugar after inversion, and 

 before inversion if it gives the qualitative test for reducing sugar before 

 it has been boiled with acid. 



From the data obtained (and taking 95 parts of cane-sugar as 

 equal to 100 parts of glucose) calculate the amount of cane-sugar 

 absorbed, left unchanged, and inverted, though not absorbed. 



(2) One and a half hours after the meal anaesthetize B, and 

 proceed as in (i). 



(3) Two hours after the meal proceed in the same way with C. 

 But in addition observe the lacteals in the mesentery, by lifting a 

 loop of intestine gently up immediately after opening the abdomen. 

 If the absorption of the fat has begun, they will be easily visible, as a 

 network of fine milk-white vessels. Also examine the gastric and 

 intestinal contents with the microscope for fat globules. Compare 

 your results on the amount of sugar obtained from the three animals. 

 Probably much more unabsorbed sugar will be found in C than in 

 B, as the lard hinders it from being dissolved. 



12. Auto-digestion of the Stomach. In some of the previous 

 experiments the stomach of an animal killed during digestion should 

 be removed from the body after double ligation of oesophagus and 

 duodenum, and placed in a water-bath at 40 C. After several 

 hours the contents should be washed out, and the mucous membrane 

 examined. It may be entirely eaten away in parts. 



13. Time required for Food to pass through the Alimentary 

 Canal. Feed a dog with bones. Keep in a special cage, and 

 observe how long it takes before the easily-recognised white bone- 

 fasces appear. 



