T. 



Generation of Heat in the Comlujiion of Fuel. \&\ 



IV. 



On the Management of Fire-, particularly iiuith Regard to the ConJfru£iion of Boilers. - 

 By Benjamin, Count of Rumfoxd*. 



HE fixth of Count Rumford's experimental elTays is divided into fix chapters. Fa the- 

 firft, the curious and interefting nature of the fubje£t is difplayed, and the importance of.' 

 ceconomy in fuel, is ftrongly impreffed. It is ftated, in general terms, that no lets than feven-- 

 eighths of the heat which might be produced and ufefully applied from any given quantity of 

 fuel is loft in the common methods of application* But not to leave the fubjeft to reft upon 

 general induction, the author proceeds to relate various interefting experiments which (hew the- 

 cfifFerence of efFeft with the fame veflel. Accordingly as the fire was applied in the common.; 

 method without confining it, or according to the improved methods of the Count, theproportions 

 of fuel required to raife the temperature of equal quantities of water, differed incomparably 

 more than common obfervers might have been led to expeiS. In this firft chapter, the 

 Count enters into the midft of his fubjefl:, Hy giving a defcription of the arrangements in the • 

 kitchen of the houfe of induftry at Munich; the conftrudtion and judicious provifions of the 

 fire-place, the form of the veflels and their covers, and the faving of heat, by caufing the fteam, 

 and even the fmoke, to perform ufeful offices. He ftates the advantages of wooden boilers in many 

 cafes, over thole of metal, and after an interefting detail of particulars, we arrive at the valuable • 

 faft, that the quantity of fuel confumed in this eftablifhmeirt is only oae-tenth part of what' 

 is required to produce like proportionalefFefls in private families. This narration is followed ■ 

 by accounts of fome of the provifions in the conftrucftion of the beft fire-places, and the figure- 

 of the boilers, and is coircluded by a confeflion, which does honour to the underftanding and- 

 the principles of the Author: namely, that the want of method in this chapter, is intentional ; . 

 that he was defirous rather of writing a ufefal book, than a fplendid performance ; for which'' 

 purpofe he rather chofe to decoy the reader into a fituation where he ftiould have an inviting 

 view of ■ the whole profpeftj than to prefent a regular feries of elementary principles to this : 

 multitude, who have neither time nor patience to labour through fo abftrufe a fubjeiSl.- 



The fecond chapter accordingly prefents us with a popular and perfpicuous account of the 

 generation of heat in the combuftion of fuel. Whether heat be matter or motion, forms no . 

 part of the prefent difcuflion ; the laws of its aftion conftitute the objeft of praftical refearch'._ 

 Whether the heat be afforded exclufively by the air, which is decompofed in combuftion, or« ' 

 not, it is evident that the quantity wift be greater or lefs, accordingly as the combuftion or. 



• In confeqiience of the letter received from my correfpondcnt 'W- fee P- 86 of the prefent volume, lap- 

 plied to Count Rumford, for permiffion to copy the engravings which conftitute plateVIlI. of the prefent number,-' 

 which he granted with the utmoft readinefs. As the whole of the prefent article confifts of abridged matter, 

 from his fixth effay, or fuch remarks and fafts as I have received from him in converfation, I have tXJUjjht it -. 

 moft proper to fubjoin his name to the title, though I have, for the fake of concifenefs, ufed my own language, , 

 and have fpoken of him, in the third perfoov 



deCo!iijjoritioa.i 



