Eicgo. °] 
DESCRIPTION of 2 PORTABLE BAROMETER 
By the Reverend GILBERT AUSTIN, 4. M. and M.R.I. A. 
Tue barometer, in the hands of modern philofophers, by the Read Dec. 
remarkable facility and fuccefs with which it has been applied “© ‘79 
to the meafurement of heights, feems to have acquired a new 
property, and to have obtained a higher degree of eftimation 
among the learned. It has therefore been thought worthy of 
every cultivation that might render it more perfect or conve- 
nient, and every attempt to improve it has been favourably 
received. 
Tue inftrument, in its moft fimple form, is moft accurate, but 
not portable. To retain its fimplicity, therefore, and render 
it portable and eafy in the application, appears the proper object 
of improvement. 
In the beft modern inftruments of this kind a confiderable 
degree of accuracy has been attained, but their conftruction is 
O 2 not 
