[ 477 I 
In' the year 1^90 a Domeftick of the Marquis de. p. 2^: 
N. coming to the Author with a hardnefs on the Fore-- 
head, which was ulcerated, very painful and rebelli- 
ous ; He feveral times cicatrized it, but all in vain ^ af- 
ter fome time it broke forth afrefb. At lengthy apply- 
ing a ftronger Cauftick than before, and impatient to. 
remove the Efcarr, ftirring i t to and fro with bis Probe 
placed on its Center, he perceived feveral white Fila- 
ments in the Interftice between it and the Flefli, which 
with the Probe lie found were hard. Then pulling 
away tl^ Efcarr with his Forceps., the ftrings came with 
it, not without a great deal of pain to the Patient.. 
Some of thefe fprang from the fide ot the Nofe, Eyes> 
others from the upper part of the Forehead ^ and when 
i^t was fcparated, chey feem'd like the ftrings at the 
Root cii. an Onyon or Leek. This was the occafion 
which fuggefted tOvM. Geudron his firft fufpicion of the 
common' Dodrine, which afcribes thefe Maladies to 
Acids ia the Blood. This Incident encouragd him to. 
make a. farther Enquiry and having difle&ed many P- ir- 
Cancerous Tumours, for thefe eight years part, he gives 
us thefe pa;rticulars, as the refult of his Obfervations.. 
Cancers are always feated in Glandulous and Ner- 
vous parts, and places where there are Lympha tick 
and Excretory Veflels. There isever found in them a 
hard callous fuhftance^ not unlike a Horn, with Blood- 
veflels difleminated thro it^ which neverthelefs are 
lefler and ftraitei^ thani before the formation of 
hardnefs. In Gancrofities of the skin there is the fame; 
callous fubftance, but it expands itfelf in a very dife- 
f ent manner,, appearing at firft like plain hard Ulcer,, 
or a (mall Wart wit^k^Cari<^ou3^ Thffe,;^ 
wii^en the Ulceration ha^.made forfie progrers, appear 
Mke^the heads, of pinsih^'tbe fle&, and are no otfaetr 
than the extremities of the ftriQg$, This fubftance, al- 
founding truaCancerSi, ^is. Gentleman thinks js^ 
