14 



Scientific Proceedings, Royal Dublin Society. 



of heat by radiation, and is provided with a little silvered cover, Gr. 

 The stem, B, is supported horizontally, and is graduated from - 5° 

 to 70° or 80° Centigrade, and reads easily to tenths of a degree 

 Centigrade. Supported immediately over the cup is a small burette, 

 C, the level of the liquid in which can be very accurately read, 



owing to the fact that only a longitudinal, narrow chink of clear 

 glass is left in the centre, the sides being of opaque enamel. The 

 mouth of the little burette is funnel-shaped, and its neck can be 

 closed by the thermometer, D, it carries, the end of the thermometer 

 bulb being ground to the neck or made water-tight by a small 

 rubber ring. This thermometer is short, but has an open scale, 

 and is graduated from about 30° to 100° C. Into the burette is 

 placed the warm water or other liquid : by loosening the thermo- 

 meter the liquid is allowed to run into the calorimeter, A, below ; 

 the mean temperature of the issuing liquid is thus accurately deter- 

 mined as it flows past the bulb. When the cup, A, is nearly full 

 the burette is closed by pushing down the thermometer, D, and the 

 cover, Gr, quickly placed over A : the highest reading on the stem, B 

 is now taken. The volume of the liquid used is then read from the 

 burette, and the operation is complete. But as the volume of the 

 liquid has been measured, its weight must be found by taking its 

 specific gravity for the temperature at which it was used. 



To obviate this inconvenience, the weight of the liquid can be 

 found directly in the arrangement shown in the figure. 



Here the thermometer is turned into a balance, the stem being 



