This is in the form of powder, and is an irritant. For use it should be thoroughly mixed with lard or vaseline. One teaspoonful of the cantharides to 4 tablespoonfuls of lard or vaseline. When so prepared it is excellent as a blister. It can be applied for sweat thickenings or lumps on any part of the body that is not on the bone. It should not be used on curbs or tumors and is not used internally.
CARBOLIC ACID
This is got from coal tar and petroleum. When full strength and pure it is in the form of crystals, but is generally bought as a liquid. It is a disinfectant and an antiseptic, and while used internally for some purposes, is largely used internally in washes and solutions. Its principal use is in bathing wounds and sores. Care should be taken not to have a wash contain too much of the acid, as it will burn the wound and stop the healing action. It is a corroding poison taken internally. It should be just strong enough to kill bacteria; say, 1 part to 1,000 parts of water. A very good healing salve is made when 5 drops of pure carbolic acid is used to 4 tablespoonfuls of vaseline.
CORROSIVE SUBLIMATE
This is used externally as an antiseptic and disinfectant. Dissolve 1 part to 100 parts of water. It is a preparation of mercury, is poisonous, but excellent for bathing wounds and open sores.
CASTOR OIL
This oil is pressed from castor beans. It is a mild physic similar to raw linseed oil. It is not used much for live stock.
Dose: For horses and cattle, 1 pint; for sheep, one-quarter pint, and for pigs, 4 tablespoonfuls.
CALOMEL
This is a heavy white powder and a mineral. Its principal action is as a physic, and it has a cleansing effect on the liver. Hence it is used for all kinds of liver troubles. When dusted in old sores, it is splendid for healing and drying up.