ABSCESS, 107 
incision, the inflammation continues and the granulating process is 
delayed. There are two ways of overcoming this stagnation of the pus, 
namely, by a larger wound or a counter opening. If the pocket is small 
and below the puncture, division of the tissues is not dangerous and the 
wound may be enlarged without danger ; otherwise counker openings 
should be made. They are necessary in deep abscesses of the throat, 
neck, poll, withers, abdominal walls, or extremities ; and if interference 
has not been made early, wide undermining soon takes place, the bottom 
of which is ordinarily far below the point of the original puncture. 
Counter openings can be made by introducing through the incision of 
the abscess a curved director, which, pushed towards the bottom of the 
pocket, raise the walls of the abscess, which are then divided from out- 
wards inwards. If the director is not used, the exact situation of the 
bottom of the pocket is made out with the finger, and at a correspond- 
ing point the skin and subcutaneous tissues are punctured from out- 
wards inwards. A fenestrated drain is then put through this second 
opening and secured. Several counter openings may be required : they 
are made ina similar way. For drainage, tents made of oakum, disin- 
fected horse-hair, or silk-worm gut are used, but the rubber tube is 
better ; the escape of the pus is easier. Injections into the purulent 
cavity, to wash it out, are also very advantageous. 
To open the abscesses of mucous cavities a long trocar or a straight 
bistoury (protected by cotton or wadding wrapped round the blade within 
two or three centimeters of the point) are used, Some abscesses of the 
rectum can be opened with the index finger thrust suddenly through the 
rectal mucous membrane, which is thin at the zone of fluctuation. For 
others, are recommended a concealed bistoury, or one used for the punc- 
ture of the vagina in ovariotomy. 
At one time the cauéery was extensively used for opening abscesses. 
‘This has the advantage of giving rise only to slight hemorrhage, and 
does not have the danger of possible slippings of the instrument, and 
therefore the cutting of nerves or large blood vessels, if the animal sud- 
denly struggles. But it will escape the blood vessels or nervous bands 
of the inflamed centre no better than the bistoury, if it be introduced 
in their tracts. If the cautery be selected, one should take a long 
pointed one, heated to white heat, place it upon the centre of the growth, 
and by a double movement of pressure and semi-rotation push it in, 
until a sensation of resistance overcome is perceived, which indicates 
that the cavity is entered. The pus sometimes escapes immediately, 
but sometimes not until the instrument is withdrawn. 
The “#ocar has been recommended for opening deeply situated 
abscesses or those of regions containing large vascular branches which 
might be divided by the bistoury ; but, like the cautery, it does not 
always escape those organs, and in the zones which arecalled “ dan- 
