JOURNAL 



OF 



NATURAL PHILOSOPHY, CHEMISTRY, 



AND 



THE ARTS. 



DECEMBER 1799. 



ARTICLE L 



An Inquiry concerning the Weight afcribed to Heat. By BENJAMIN CoUNT OF 

 RuMfORD, F. R.S. M. R.LA. &c,* 



* U *HE various experiments which have hitherto heen made with a view to determine 

 -'*' the queftion fo long agitated, relative to the weight which has been fuppofed to 

 be gained, or to be loft, by bodies upon their being heated, are of a nature fo very 

 delicate, and are liable to fo many errors, not only on account of the imperfcftions of 

 the inftruments made ufe of, but alfo, of thofe, much more difficult to apprtciate, 

 arifing from the vertical currents in the atmafphere, caufed by the hot or the cold body 

 which is placed in the balance, that it is not at all furprifing that opinions have been fo 

 much divided, relative to a faft fo very difficult to afcertain.. 



It is a confiderable time fince I firft began to meditate on this fubjeft, and I have 

 made many experiments with a view to its inveftigation ; and in thcfe experiments, I 

 have taken all thofe precautions to avoid errors, which a knowledge of the various 

 fources of them, and an earneft defire to determine a faft which I conceived to be of 

 importance to be known, could infpire; but, though all my rcfearches tended to con- 



* Philof. TranC 1799. page 179. 



Vol. III. — December 1799. 3 D* vince 



