By PRor. EMERSON REYNOLDS, M.D. AL 
for the estimation of urea by the hypobromite method, and, with 
a little modification, for the estimation of carbonic acid in car- 
bonates, and for other similar purposes. I shall only refer at 
present to its use in ureometry. In this apparatus the nitrogen 
evolved is directly measured as gas under conditions which admit 
of very accurate determinations of volume in cubic centimetres. 
The apparatus is shown in section in Fig. 2. The stand A 
supports a tall glass cylinder B. Through the large india-rubber 
cork which closes the lower opening of the cylinder the U tube c 
is passed, great care being taken to avoid breaking the small T 
connector c. The outer limb of the U tube is provided with a 
glasstap T. The limb within the tall glass cylinder is sufficiently 
wide to contain 150 cubic centimetres in the expanded portion, 
which, in my apparatus, measures sixty centimetres in length. 
The graduation cannot be conveniently carried beyond fifths of 
a cubic centimetre. At the point shown an india-rubber tube g 
is attached, which can be closed at will either by a good clip or 
by a stopper of glass rod. The glass side tube c serves to con- 
nect the measuring apparatus in the manner shown with the 
generating vessel D, which is a long and wide glass tube placed 
within the cylinder. The glass T tube E is connected by means 
of rubber tubing with c, while one limb passes through the india- 
rubber cork of D, and the other is connected by another piece of 
rubber tubing with the fine tube of the long pipette F (of about 
20 ec. capacity), which projects through the cork. This con- 
-nexion must be sufficiently long to admit of the clip being 
applied as shown. 
The large glass cylinder B is filled with water, in order to 
maintain a steady temperature, the value of which can be known 
by means of a thermometer immersed in the water. 
A determination is made with this apparatus in the following 
way :—Having disconnected the T tube E from ¢ and the clip, 
the generating tube D is taken out of the water of the 
cylinder, the cork carrying the pipette, &c., withdrawn, and then 
five cubic centimetres of the urea solution introduced into the tube 
D. Before replacing the cork the pipette F is filled with hypo- 
bromite solution by suction above H, while the small glass tube 
opening on the under side of the cork is closed by a finger; the 
