226 3ULPHT7RE* OF LEAt>, COPPER, AND ANTIMONY. 



mine on the endellion, which was printed in the first part 

 of the Transactions for 1804. It may appear strange, par- 

 ticularly to those who have read Mr. Smithson's sharp cri- 

 tique, that I have so long delayed answering it: but this 

 delay was owing to one of those peculiar circumstances, 

 happily not very frequent, which the mind is as unable t» 

 foresee, as prudence is to avoid. Chance made me ac- 

 quainted with the criticism of Mr. Smithson, at the time 

 of its being delivered to the secretary of the Royal Society, 

 Dr. Wollaston, at whose house I then happened to be. He 

 gave me permission to lock it over. Its nature surprised 

 me; and this was all the impression it would have made on 

 me, had I not immediately felt the disagreeable necessity I 

 should be under of answering it, if it should be admitted 

 into the Transactions of the Royal Society ; a circumstance, 

 which I could never have supposed would take place, had 

 I not had some particular reasons to be apprehensive of it. 

 I requested in consequence Dr. Wollaston to favour me 

 with a copy as soon as it should be printed ; which he pro- 

 mised me. Some time after, being at the house of the 

 same gentleman, whom I was frequently led to vit-it by the 

 esteem and attachment I felt, I found on his table the cor- 

 rected proofs of this very paper, and then reminded him of 

 the 'promise he had made. In fact lie sent me a copy soon 

 after. Happily I had in readiness the materials necessary 

 to render my answer in some degree interesting, and pre- 

 vent my feeling the irksomeness commonly attendant o» 

 Farther know- writings of this kind. After I had written my former pa- 

 ledge of the p er> J had obtained a knowledge of this substance, at that 

 compound su!- . , , . , , , 



j/huret obtain tiale ^tremely scarce, and considerably so even at present,. 



ed by the a a- that enabled me to render my account of it far more com- 

 plete: and this indeed I had for some time had an inten- 

 Account of 'it tibn of doing. A pursuit however in which I was then en- 

 deliverwltothe paired, and which I could not interrupt, did not allow ma 



secr«taryof the ? ° .. . r •/ , ■« . . , ' . 



Royal Society, immediately to draw up the memoir I had in contempla- 

 tion : and it was not till about the month of September, in 

 the same year, 1808, that I was- able to deliver it to the 

 secretary of the Royal Society ; expressing at the same time 

 my wish, that it might be read as early as possible, in order 

 that at least it might obtain a place in the first part of the 



Tiasnactions 



