on sawing through a bone to which it adheres, I have occasionally found that a distinct line of demarcation is visible between the bone and the affected periosteum.
Periosteum, which has become ossified, does not seem to enjoy so high a degree of vitality as exostosis, and upon this circumstance the surgeon founds his plan of treating it; hence we now and then hear of cure by means of the cautery, rubefacients, &c. of what some practitioners have termed Periosteal Exostosis.
SECTION II.
SUPERFICIAL INFLAMMATION OF BONE.
It is a difficult matter to give a description of the pathological characters of simple inflammation of the surfaces of bone, as it seldom exists uncombined with periostitis, or it spreads, before we have an opportunity of examining its specific characters, to the internal structure of the bone. But, nevertheless, appearances occasionally present themselves, which are sufficiently well marked to war-
