APPENDIX, 

 fcale is of a magnitude equal to almoft 414 degrees of 

 the fcale. 



If we have the height of both the manometer and ther- 

 mometer, the height of the barometer may be thence de- 

 duced by this rule ; as the height of the manometer in- 

 creafed by 414, is to the height of the thermometer in- 

 creafed by 414 ; fo is 29,7, to the height of the barometer. 



This inftrument, though far from complete, having 

 been conftruded in a hurry for the purpofe of a firft expe- 

 riment, and liable to fome inaccuracies in the obfervations 

 from not having the thermometer with which it was com- 

 pared attached to it, feldom differed from the marina 

 barometer nV of an inch. Should it be improved to that 

 degree of accuracy of which it feems capable, it will be of 

 great ufe in determining refractions for ailronomical obfer- 

 vations, as well as indicating an approaching gale of wind 

 at fea.- 



129 



U Meteorolocrical 



O 



