[ 5 *° 3 
means the neceflary Motions of the Body are per- 
formed without Pain. 
If vvc confult the ftandard Chirurgicai Writers 
from Hippocrates down to the prefent Age, we fhall 
find, that an ulcerated Cartilage is univerfally allowed 
to be a very troublefomc Difeafe ; that it admits of a 
Cure with more Difficulty than a carious Bone ; and 
that, when deftroyed, it is never recovered. Hildanus> 
in confidering thefe Difeafes, has obferved, that when 
the Cartilages of a Joint were deftroyed, the Bones 
commonly threw out a cementing Callus ; and thus 
a bony Anchylojis , or immoveable Continuity, was 
formed where the moveable Joint had been. So far 
as I have had Opportunities of examining difeafed 
Joints, either after Death or Amputation, I have 
found, according to the Nature and Stage of the 
Difeafe, the Cartilages in fome Parts redifh and lax ; 
or foft and fpongy ; or raifed up in Blifters from the 
Bone ; or quite eroded, and, perhaps, the Extremities 
of the Bones carious ; or, laftly, a bony Anchylofis 
formed. But I could never fee, nor indeed hear of, 
the lcaft Appearance of an Exfoliation from the 
Surface of the Cartilage. Now, if we compare the 
Texture and morbid Phenomena of thofe Cartilages 
together, all the difeafed Appearances will admit of 
as rational a Solution, as perhaps any other Part of 
the vitiated Oeconomy. 
It appears from Maceration, that the tranfverfe 
Pibrils are extremely tender and difl'oluble ; and that 
the Cohefion of the Parts of the ftrait Fibres is ftronger 
than their Cohefion with the Bone. When a Car- 
tilage therefore is inflamed, and foaked in purulent 
Matter, 
