264 Fourcroy’s Extamination of 
tions and faéts which fhew, that the author feems not fo 
have accurately comprehended the labours of Scheele. and 
that he feems to have overlooked the refearches which I 
publifhed on the fame fubjeGt, though he quotes me in re- 
gard to fome facts, but only as one of thofe who may be 
confidered as almoft a ftranger to the object which he, had_ 
in view. It alfo appears to me, that the experiments he 
made, inftead of contradiGting the facts obferved by Scheele 
and myfelf, and the confequences I have thence. deduced in 
regard to the nature of urinary concretions, are rather cal- 
culated to confirm them, 
~ What I mean to eftablifh in this memoir requires, rf, 
That I fhould give an exact account of Dr. Pearfon’s experi- 
ments: 2d, That I cormnpare with his refults the facts ob- 
férved by Scheele and Bergman; and that I add to them’ 
thofe which I obferved myfelf: and, 3d, That I draw from 
this comparifon thofe indugtions which form the princi- 
pal part of this memoir. 
The firft pages of this differtation contain a very concife 
account of the labours of Scheele, Bergman,  Fourcroy, 
Link, and Black, But I muft here obferve, that this fhort 
notice is far from being fufficient to give an accurate idea of 
thefe labours; that it is very fingular to hear Dr. Pearfon 
fay, that the particular matter of which he intends to fpeak, 
and which be fays he obtained by diffelving concretions in 
ley of fixed cauftic alkali and precipitating it by means of 
acids, was confidercd as of little importance by Scheele, 
who, he fays, of courfe never made any refearches in regard 
to its propertiés; whereas, if we read with attention the 
miafterly diflertation of the Swedifh chemift, we fhall find’ 
that it was this matter which he confidered as his real acid 
of calculus, and which we have fince called the Jithic acid, 
I inyfelf have feveral times announced in my works, parti- 
cularly under jhe article of cilculus in the DiGionnaire de 
Chimie Encyclopedique, iferted in, the Annales de Chimie, 
1793, tom. xvi. that it was thus that I prepared: the lithic, 
acid 
