474 
R. H. HARRISON. 
is by far more rapid and that it leaves a cicatrix scarcely notice¬ 
able. 
The case referred to was a valuable running horse, a sorrel 
gelding, eight years old ; he was affected with a discharge from 
the left nostril and an accumulation of pus in the sinuses of the 
same side. He was trephined first at the nasal sinus, an ordinary 
instrument being used, which was of .arge diameter, and had coarse 
teeth; a day or two after the superior maxillary sinus was 
opened with a small instrument having fine teeth. The latter, as 
soon as the accumulation of pus ceased, closed up quickly, and 
left but a slight cicatrix. The nasal opening at first appeared to 
be doing finely, closing rapidly. Two days after cicatrisatmn had 
taken place, a slight swelling was observed an inch from the 
opening and nearer the median line, very tender to pressure and 
rapidly increasing in size. This proved to be an abscess, which 
was opened and cleaned by antiseptic injections of carbolic solu¬ 
tion ; this abscess closed, but another formed in close proximity 
to it, which was opened and pus evacuated ; also two small pieces 
of bone were removed. Inserting a probe, it was found that 
these abscesses connected with each other, and with the nasal 
opening, by fistulous tracts, and that the bone was denuded of its 
periosteum; injections of carbolic solution were forced through 
the tracts for a few days, which resulted in the cleaning of the 
tract leading from the nasal opening to the first abscess. Another 
tract formed, however, from which another abscess resulted 
within an inch of the eye, on a horizontal line with the last, was 
opened as before, together with the fistula; finally another abscess 
and tract formed near the external canthus of the right eye. This 
was opened and a minute piece of bone removed, after which the 
parts healed without difficulty. As a result a sort of traveling 
periostitis was set up, proceeding from the left to the right, which 
gave rise to bony deposit along the line of the fistulous tract, 
more marked where the abscesses had formed than in other 
places. The probable explanation of this condition is, that a 
minute fragment of bone, detached by the trephine, had imbedded 
itself under the skin, and had tried to work its way out, being 
prevented from escaping by the too rapid closing of the wound. 
