ON PURE NICKEL. 75 



fent to them by colder furrounding bodies the more or lefs per- 

 fect polifti of their furfaces, ought not fenfibly to influence the 

 rapidity of their cooling. 



This is precifely what all my experiments concur to prove. Experiments 



I have long fought, and with that patience whicH^he love H°™ 1S P 01< 

 of the fciences infpires, to reconcile the relults of my experi- 

 ments with the opinions generally received concerning the na- 

 ture of heat and its mode of a&ion, but without being able to 

 fucceed. . * * 



It is in the hands of two of the moft illuftrious bodies of 

 learned men that ever exifted that I have thought it incumbent 

 on me to depoiit my labours, my difcoveries, my doubts, and 

 my conjectures. \jf . 4^^ 



I am earneftly defirous of engaging the philofophers of all 

 countries to turn their attention towards an object of enquiry 

 too long neglected. *^%LlJ^* * \m 



The fcience of heat is not only of great curiofity, from the Importance of 

 multitude of aftonilhing phenomena it offers to our contempla- f facnce ot 

 tion, but it is Iikewife extremely intereiling from ils intimate 

 connection with all the ufeful.arts, and generally with all the 

 mechanical occupations of human life. 



Without a knowledge of heat it is not poffible either to ex- 

 cite it with economy, or to direct its different operations with 

 facility and precilion. lrffc '^ w 



(The Remainder in our next.) 



II. 



- 

 On pure Nickel, djfeovered to be one of the noble Metals, and on 



its Preparation and Properties. By J. B. Richter.* 



VJ'N repeatedly cryftallizing fulphate of ammonia and nickel, Cotalt feparated 



the whole of the cobalt, an extremely fmall quantity excepted, trom {a }P hit * of 



.... J i v J ft ammonia and 



will be (eparated; but after this there ftill remains fome cop- nickel by re- 



per mixed with the fait. I have already announced that this P ea . ted cr y ftall »- 



metal may be feparated from the nickel by fubliminglfee latter Copper, by fub- 



with fal ammoniac; but at that time I had nevew^)btained ,imin S with fat 



pure nickel. With the compound fait of nickel and ammonia 



if 



* Tranflated from the Journal de Chimie of Van Mons, vol. VI. 

 p. 183, March, 1805; and abridged by Van Mons from the All- 

 lemeines Journal der Chevi'ie^ 1804, vol. III. p. 244. 



2 a little 



