Mr. ches ton’s Continuation , See. 579 
refinance I felt in the body of the tumor, was not from 
its paffing through a carious or difeafed part, as there 
was reafon then to fuppofe, but from the quantity of 
offeous matter depofited on the outward fide of the os 
innominatum', and that the part fo loaded with it exter- 
nally, and as it afterwards proved to be internally , was 
apparently in a found Itate. 
It is difficult to fix upon the precife part where the 
tumor occupying the right moiety of the pelvis , and con- 
taing the boney matter, originated. There is, however, 
every reafon to fuppofe it began low down in the pelvis 
under the peritoneum , as the furface of the tumor was 
evidently covered with that membrane; and from every 
circumftance in the appearance of the tumor, as well as a 
careful examination of it, during the progrefs of its dif- 
folution, it is probable, that paffing out of the pelvis an- 
teriorly through the foramen ovale , as well as laterally 
under the ifehium , and riling upwards over the fpine of 
the ilium , it formed a complete communication from 
within outwardly, fo as to envelope the whole of the right 
os innominatum entirely. 
As the foft parts of the tumor decayed in mace- 
ration, great quantities of boney matter in irregu- 
lar forms and of different fizes were found in the water 
at the bottom of the pan; and as no force, nor even 
Vol. LXX. 4 G motion. 
