and Laboratory Methods. 



1287 



Directions for Use. — Fill the ^tube with water to the mark A. In doing 

 this, put the index finger on the end of the side-tube rt'and fill the limb B. By 

 inclining the (7 tube, the water is 

 forced into limb C, and any air bub- 

 bles are removed in a similar manner. 

 As soon as the tube is filled to the 

 mark close the free end of £ with a 

 cork or a rubber stopper. This pre- 

 vents the water from running out 

 through the side-tube. Put 20 c. c. 

 of the' hypobromite solution into the 

 flask £, replace the double-perforated 

 rubber stopper g, insert the side-tube 

 ti into one perforation and the pipette 

 / filled with urine into the other. 

 Remove any air bubbles from the 

 limb C by inclining the apparatus, 

 taking care that none of the hypo- 

 bromite solution comes in contact 

 with the urine. Remove the cork from 

 the free end of limb B. Open the 

 stop-cock on the pipette, allowing 1 

 c. c. of urine to flow into the flask. 

 The iV accumulates at the closed grad- 

 uated limb C. Gentle shaking of the 

 apparatus will greatly hasten the reac- 

 tion. 



The hypobromite solution is best made up extemporaneously. The follow- 

 ing method will be found most serviceable : Have on hand a saturated solution 

 of sodium hydrate. Place 10 c. c. of the latter into the flask and add 1 c. c. of 

 bromin. Shake gently until reaction is complete and add 10 c. c. of water. The 

 writer's way of taking up the bromin will no doubt be appreciated by those who 

 have had their Shneiderian membrane frequently exposed to the irritating vapors 

 of this dangerous substance. We use the ordinary 1 c. c. pipette, to which a long 

 piece of rubber tubing is attached. On the latter, somewhere near the end, is 

 placed a small Hoffman clamp. The bromin is sucked up to the mark and the 

 clamp at once closed tightly by means of the screw. The end of the pipette is 

 then carried at once into the sodium hydrate solution, and the bromin discharged 

 slowly by opening the clamp. As a safe precaution we keep open a bottle of 

 ammonia during the operation. 



To use this apparatus as a saccharometer the double-perforated stopper is 

 replaced by one with a single perforation. The 6^ tube is filled with water as 

 described above, 10 c. c. of diabetic urine put in the flask, 1 grm. of Fleishman's 

 yeast added, together with a small crystal of tartaric acid, and the apparatus set 

 aside for 24 hours. The CO 2 generated will collect at the closed end of limb C. 



Fermentation Tubes. — On the same principle the writer devised a fermen- 



Fig. I. 



Combined Ureometer and Saccharometer 

 set up as Ureometer. 



