1865.] 



of Water and Mercury. 

 TABLE I. 



553 



IV. On the redeterminatioa of the coefficient of expansion of mercury. 

 The pure mercury was weighed in a bucket in the water at different 

 temperatures. The glass bucket was made from the end of a test-tube (its 

 length being about 20 millims. and width 15 millims.). The expansion of 

 this sort of glass was found to be 



V,=V (1 + 0-0000256G*). 



Five series were made with mercury ; and its expansions, deduced from 

 the water-expansions given in Table I, were 



Series I ....... V,=V (1 +0-00018150, 



Series II ....... Vi=V (1+0-0001813*), 



Series III ....... V*=V (1 +0-0001808*), 



V,=V 



-00018080, 



Series IV 



Series V ....... V;=-V (1 +0-00018160, 



Mean ____ V,=V (1+0-00018 12*), 



a value closely agreeing with Rcgnault's, namely 

 V =Vo (1+0-00018150- 



