ESSAY XXIII. 



ON THE INFLAMMABLE PRINCIPLE IN CRUDE 

 CALCAREOUS EARTH. 1 



You entreat me, my worthy friend, to communicate to you 

 my thoughts on Dr. Weber's publication, entitled The Nature 

 and Properties of Lime and Caustic Substances newly discovered. 

 I cannot but wonder that the controversy concerning fixed 

 air and the acidum pingue should not yet have ceased with 

 you. That this acid is a mere chimera, is acknowledged 

 both by Dr. Weber and, I believe, by all chemists. But it 

 would appear that the Doctor wishes, by his phlogiston, to 

 supplant fixed air, as this has supplanted the acidum pingue. 

 Whoever is desirous of attempting satisfactorily to prove 

 any opinion in chemistry, ought to be thoroughly acquainted 

 with the bodies with which he makes his experiments, and 

 on which he rests his proofs. But when this knowledge is 

 wanting, how easily may wrong conclusions be drawn ! I 

 do not indeed by any means flatter myself that we are 

 acquainted so completely as could be wished with the 

 constituent parts of all bodies, but so much is certain, that 

 all oily compounds, derived from the animal and vegetable 

 kingdoms, yield, when they are entirely destroyed, an 

 inflammable principle, a mild acid in an elastic form, or the 



1 This is a letter from Mr. Scheele to Mr. Meyer of Stettin. The 

 original was published in Crell's Neuesten Entdeckungen, Th. 1, 

 p. 30, etc. 



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