Experiments oh the Tranfmijfton of Heat through Fluids. $ft : 



This experiment feems to me to prove, in a very clear manner, that water is a con- 

 duftor. But before we draw any fuch conclufion from it, or from thofe before detailed, it 

 will be proper to enquire whether the rifing of the thermometers can be accounted for in 

 any other way. If it cannot, then water and mercury muft be confidered as conduftors. 

 Now, it may be faid, that the thermometers rofe in confequence of the aftion of tranfmitted 

 caloric ; or that caloric was conduced to them by means of the glafs vcflel in which the ex- 

 periment was made ; or that currents of the hot liquid made their way to them ; or, laftly> 

 that the cold liquid was thrown into fuch agitation by the pouring in of the hot liquid over 

 it, that currents of it heated direftly by the contaft of the hot liquid made their way to the 

 thermometers. If none of thefe fuppofitions will account for the rife of the thermometers, 

 we muft conclude from- the experiments that mercury and water are condu£lors of 

 caloric. 



I , If the thermometers had rifen in confequence of caloric tranfmitted to them through 

 the cold liquidf,, they ought to have begun to rife at the fame inftant ; or, rather, the loweft, 

 which was die moft delicate, ought to have begun to rife firft. But the contrary is evident 

 from all the experiments. In the laft experiment, for inftance, the thermometor B did not 

 begin to rife till fome time after the oil had been poured in ; and thermometer C not till 

 more than 6' after I had begun to obferve the thermometers, and, confequently, not till 

 jX kafl: 12' after beginning to pour in the oil. Thermometer B reached its maximum ia 



21',. 



