﻿Connective Cooling in Fluids. 



927 



supply necessary to maintain a measured temperature 

 difference between the wire and the general body of the 

 liquid. The electric energy supplied was determined from 

 the measured current through the wire, and from its 

 resistance as obtained from a Wheatstone bridge. This 

 resistance also gave the temperature of the wire. 



lor each of the liquids the cooling of wires of two sizes 

 was studied, the diameters being 0*0083 cm. and 00155 cm. 

 respectively. Both were thought to be pure platinum, but 



Fie-. 1. 



tests of the resistance at the temperature of melting ice and 

 that of steam gave a very low value for the temperature 

 coefficient of the finer wire. 



The aDparatus is shown diagrammatical ly in tig. 1. Ine 

 platinum wire TT, immersed in the liquid under examination, 

 formed part of the fourth arm of a Wheatstone bridge, 

 having equal ratio arms PP. By adjusting the slider S the 



