RegnauWs Researches upon the Dilatation of Gases. 



65 



mercury, but the mercury not coming completely in contact with 

 the tube, there would be a small portion of air adhering to it, 

 and as the mercury would rise in the tube, the air would enter 

 with it, and this is what Regnault here calls the phenomenon of 

 aspiration ; this he avoided by surrounding that part of the tube 

 that was immersed in the mercury with tinfoil, and also by pour- 

 ing a quantity of concentrated sulphuric acid upon the surface 

 of the mercury. 



Second method : the results obtained by this method are 



1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 Then 



Third 



1 



2 



3 



4 



5 



6 



1.36629 

 1.36645 

 1.36593 

 1.36610 

 1.36585 

 1.36590 

 1.36615 

 1.36591 

 1.36708 



10 



11 

 12 

 13 

 14 

 15 

 16 



17 



18 



1.36695 

 1.36633 

 1.36708 

 1.36650 

 1.36615 

 1.36594 



1.36660 

 1.36666 

 1.36614 



ean of these experiments is 1.36633. 

 nethod : the results by this method are 



1.36688 

 1.36688 

 1.36612 

 1.36643 



1.36651 

 1.36626 



7 



8 



9 



10 



11 



12 



1.36649 

 1.36672 

 1.36714 

 1.36714 

 1.36730 

 1.36747 



The mean of these experiments is 1.36679 



Fourth method. 



1 



2 



3 



1.36592 

 1.36710 



1.36662 



4 

 5 



6 



1.36682 

 1.36674 

 1.36580 



The mean of these is 1.3665. 



The following are the results of the four different methods 



First series, 

 Second series, 

 Third series, 

 Fourth series, 



1.36623 

 1.36633 

 1.36679 

 1.36650 



Mean, 



Vol. xliv, No. ].— Oct.-Dec. 1842. 



1.3665 



9 



