6io A MANUAL OF PHYSIOLOGY J 



first trace of sugar and albumin. If a sufficient amount of urine is 

 obtained, the quantity of sugar in successive specimens may be 

 estimated and compared. The rate of flow of the urine as measured 

 by the number of drops falling from the catheter may also be esti- 

 mated from time to time, in order to determine whether diuresis is 

 taking place. 



If a rabbit is used for this experiment, the sugar solution may 

 be injected into the ear vein. The vein is caused to swell up by 

 pressing on it with the finger and thumb, and the hypodermic needle 

 is then inserted towards the heart. 



(b) Instead of collecting the urine by a catheter in the bladder 

 the abdomen of the dog may be opened, and a cannula tied into 

 each ureter. The two cannulae are then connected by short rubber 

 tubes with a glass Y-piece, on the stem of which a test-tube is tied 

 for collecting the urine. Replace the test-tube by a fresh one from 

 time to time. The urine already in the bladder is removed by 

 pressure or by a trocar, and tested for sugar, since the anaesthetic 

 itself may cause a certain amount of glycosuria. Test the samples 

 of urine obtained from the ureters for sugar, and in those in which 

 it is present estimate its amount. Note also any changes in the 

 rate of secretion of urine, and any abnormal constituents, as albumin. 



(2) Phloridzin Glycosuria. Dissolve grm. of phloridzin in warm 

 water, and inject it subcutaneously into a rabbit. Obtain a sample 

 of the urine at the end of two hours, by pressure on the abdomen 

 with the thumb or by passing a catheter, and test for sugar. If none 

 is present, wait for another interval, and again test the urine. 



This experiment can also be performed without risk on man. 

 One grm. of phloridzin has been injected twice a day without dis- 

 turbing the individual. Much sugar is found in the urine, but it 

 disappears the day after the administration of phloridzin is stopped. 

 The phloridzin may also be given by the mouth, but more is required, 

 and it is not very easily absorbed, and often causes diarrhoea 

 (v. Mering). 



(3) Alimentary Glycosuria. The urine having been tested for 

 sugar for two successive days, and none being found, 



(a) A large quantity of dextrose is to be taken in the form which 

 is most agreeable to the student some hours after a meal. The urine 

 of the next twenty-four hours is to be collected and measured. A 

 sample of it is then to be tested for reducing sugar by Trommer's and 

 the phenyl-hydrazine test. If any sugar is found, the reducing power 

 of a definite quantity of the urine is to be determined by titration 

 with Fehling's solution (p. 489). 



(b) Instead of dextrose use cane-sugar and proceed as in (a) . But 

 estimate the reducing power of the urine (a) before and (0) after 

 boiling with hydrochloric acid (p. 433). 



(c) A large meal of rice and arrowroot, sweetened with as much 

 dextrose as the observer can induce himself to swallow, is to be 

 taken, and the urine treated as in (a) . 



(d) A large number of sweet oranges may be eaten.* 



4. Milk. (i) Examine a drop of fresh cow's milk with the micro- 

 scope. Note the fat globules of various sizes. 



(2) Determine the specific gravity of the milk with a hydrometer 

 (lactometer) . Then centrif ugalize some of the milk to separate the 

 cream, which rises to the top of the tubes. Remove the cream and 



* These experiments may be distributed among the class so that each 

 student does one, 



