128 DESCRIPTION OF AN ENCHONDROMATOUS TUMOUR. 
stance resembling cartilage consists of cells, and an amorphous 
intercellular material. The cells are large, mostly oval with 
compound nuclei, and vary in size from to -3-^ of an inch 
in long diameter, which is about a third greater than their 
tranverse measurement; some of the cells are considerably 
larger than even the greatest of these dimensions, and contain 
smaller cells within, which latter possess single nuclei. In 
places where the tumour is soft the cells are fewer in number, 
and the intercellular substance contains numerous molecules and 
granules. The cell walls are more plainly defined, and the 
intercellular substance is softer in consistence than in any kind 
of ordinary cartilage. Acetic acid produces results on the cell 
walls and their nuclei precisely the same as those witnessed in 
any kind of healthy cartilage when similarly treated.” 
On examining the remaining thoracic viscera, the apex of the 
heart was found adherent to the pericardium, which was con- 
siderably thickened at their surfaces of attachment ; one of the 
pulmonary semilunar valves was covered and corrugated by 
fibrous deposit; and the same membrane of the artery was 
encrusted by detached calcareous deposits about one-eighth of 
an inch in thickness and half-an-inch in circumference. 
The occurrence of enchondromatous tumours in connexion 
with bone may frequently be traced to some mechanical injury, 
as blows, contusions, wounds, &c., and their development may 
be considered as, in part, due to a perversion of nutrition, which 
induces us to believe the tissue subsequently formed at the seat 
of injury to be a growth of degeneration, or approach to a stage 
of organization lower than that naturally belonging to the part they 
affect : this mode of explaining their probable origin, however, 
scarcely applies when these tumours are found developed in other 
tissues besides bone. What the originating cause is, and why they 
should be occasionally developed in the parotid and mammary 
glands, and, in the case under notice, within the lungs, we can 
but speculate at the best, and then our deductions are not so 
satisfactory as we would desire. Science, however, will still 
continue to investigate ; and ere long, I doubt not, more light 
will be thrown on the origin of these products when associated 
with glandular structures. 
I am, Sir, respectfully. 
Your obedient servant. 
