106 VETERINARY SURGICAL THERAPEUTICS. 
a free cut is required. For some deep abscesses, especially in the 
regions where organs exist which must be respected, the tissues should 
be divided layer by layer; in some cases, it is wise, where once the skin 
is cut, to lay the bistoury aside and divide the tissues underneath with, 
he grooved director, the incision being afterwards enlarged with the 
scissors or a blunt blade. In general, the incision is made parallel to 
the muscles and to the vasculo nervous trunks of the region. 
When one opens an abscess of the canon, fetlock or digital region 
the sharp edge of the bistoury must always be directed towards the 
shoulder. If it is directed towards the foot, and the animal, not suffi- 
ciently under control, or irritated by the pain, should move his leg 
suddenly, the tissues might be divided deeply and extensively ; and if 
the abscess is on the sides of the fetlock, the digital blood vessels might 
be opened, the ligaments or tendons cut, and the articulation opened. 
We have seen in this way the division of the digital artery. 
There are.regions where a puncture, as simple as it may appear, 
gives rise to serious results when it is not methodically performed. 
Before plunging the instrument into the abscess, one must take 
into consideration the exact situation of the blood vessels, and bear in 
mind that those may be displaced by the purulent collection. In push- 
ing the bistoury deeply into such regions, an artery, a vein or a nerve 
may be wounded, and as the result, a hemorrhage difficult to control, or 
paralytic accidents may follow. Suppurative phlebitis has been more 
than once the consequence of punctures made without sufficient care. 
The opening of the abscess must be made in the most dependent 
point, so as to allow the free exit of the pus. It is not necessary that 
it should be large ; the discharge keeps it open until cicatrization is 
complete. The custom of introducing the finger into the cavity to 
break the band that may be found in it is not necessary, since in this 
way tissues which may serve for cicatrization are destroyed, or vascular 
or nervous branches torn. An examination of the cavity ought not to 
be made except for the sake of finding out the arrangement of its parts, 
or of seeing whether it contains foreign bodies, has cul-de-sacs, or con- 
tains pockets where the pus, collecting, may give rise to purulent infil- 
trations. When the puncture is made at the lower point, and the pus 
escapes as it is formed, recovery follows quickly. But if the purulent 
cavity is large, it is advantageous, after it has been washed with an 
antiseptic solution, to place in the opening a “rubber drain” with 
thick walls, and sufficiently large to allow the running through it of the 
albuminous masses, clots, or remains of necrosed tissues. This drain 
is fixed to the cutaneous borders of the wound by a suture of a stitch or 
two. 
In regions where there are pockets, more or less deep, in which the 
pus collects, and cannot be squeezed out except by pressure below the 
