182 The Management and Discases of the Dog 
or cold ; there is opacity of vision, and conjunctival conges- 
tion. The condition, however, is less irritable than in 
simple or acute ophthalmia. , 
Treatment.—Tonics ; seton in the poll ; painting the out- 
side of the orbits with iodine ; sponging the eyes with cold 
spring water ; the application of zinc lotion, 2 grains to the 
ounce of water, or nitrate of silver 1 grain to the ounce, 
are the measures usually adopted and indicated. The 
seton is especially invaluable in these cases. If corneal 
ulceration exists, the application of the dry oxide of zinc 
has almost a specific effect, and may be repeated daily 
until the eye is perfectly clear. 
CATARACT. 
Cataract may be either lenticular, capsular, or capsulo- 
lenticular. It is lenticular when there is opacity of the 
crystalline lens, capsular when the opacity is confined to 
the capsule, and capsulo-lenticular when both lens and 
capsule are involved. 
Though more frequently seen in old dogs, cataract may 
take place at any age. 
Causes—Inflammation of the eye-ball; diminished 
vitality, consequent on old age. 
Symptoms—The presence of an opaque body, which may 
be best seen from a posterior side view in a shaded light, 
or in a dark place by candle-light. 
Treatment.—This consists entirely in the operation of 
extraction, and which only can be performed by an ex- 
perienced oculist. 
AMAUROSIS. 
Amaurosis, commonly known as gutta serena, is an im- 
pairment of vision consequent ona disordered condition of 
the retina, optic nerve, or brain. This disordered condition 
may proceed from external violence, as blows or falls on 
