A 



JOURNAL. 



OF 



NATURAL PHILOSOPHY, CHEMISTRY, 



AND 



THE ARTS. ' 



MAY, 1806. 



ARTICLE I. 



Account of a simple and cheap portable Barometer, with In- 

 st ructions to enable a single Observer to determine Heights 

 by that Instrument with considerable Facility and Precision. 

 In a Letter from ^iK li, C. Englefield, Barf. M.P. 

 F. R. S. SjC. Sfc. 



To Mr. NICHOLSON. 

 SIR, 



T. 



H E mensuration of heights by the baronicter has been, Though the 

 by the labours of Mr» De Luc, Sir George Shuckburg, Gene- j^^l /^^ ^ ^^^ 

 ral Roy, and several other scientific men, brought to such per- haiometer has 

 faction, and affords so much an easier mode of ascertaining the p^rfofted vet 

 elevations of the different parts of the surface of the earth to the obsena- 

 a considerable precision, than any other known, process, that it ^ 

 might have been supposed that, in the course of thirty ye^rs 

 which have elapsed since this branch of science has been per- 

 fected, a very great number of observations would have been 

 made, and the heights of almost the whole surface of our own 

 ^ountry ascertained by the numerous travellers who continu- 

 VoL. XIV.— May, 1806. B ally 



