MEDICINE. 501 



For some important remarks on the composition, application and management 

 of the blister, see page 432. 



BOLE ARMENIAN is an argillaceous earth combined with iron, and is supposed 

 to possess some astringent property. The propriety of its being adminis- 

 tered inwardly is doubtful; for it may remain in the intestinal canal, and become 

 the nucleus of a calculus. On account of its supposed astringency, it is em- 

 ployed externally to give consistence to ointments for grease. Even the bole 

 Armenian has not escaped the process of adulteration, and is largely mixed with 

 inferior earths. The fraud may be suspected, but not satisfactorily detected, 

 by the colour of the powder, which should be a bright red. 



CALAMINE. See ZINC. 



CALOMEL. See MERCURY. 



CAMPHOR is the produce of one of the laurus species, a native of Japan, and 

 too often imitated by passing a stream of chlorine through oil of turpentine. 

 According to Professor Morton, it is a narcotic. It diminishes the frequency of 

 the pulse, and softens its tone. When long exhibited, it acts on the kidneys. 

 Externally applied, it is said to be a discutient and an anodyne for chronic 

 sprains, bruises, and tumours. The camphor ball is a favourite one with the 

 groom, and occasionally administered by the veterinary surgeon. Mr. W. C. 

 Spooner uses it, mixed with opium, in cases of locked jaw, and in doses of from 

 one to two drachms. In the form of camphorated oil, it promotes the absorption of 

 fluids thrown out beneath the skin, the removal of old callus, and the suppling 

 of joints stiff from labour. Combined with oil of turpentine it is more effective, 

 but in this combination it occasionally blemishes. 



CANTHARIDES are the basis of the most approved and useful veterinary blisters. 

 The cantharis is a fly, the native of Italy and the south of France. It is de- 

 stroyed by sulphur, dried and powdered, and mixed with palm oil and resin in 

 the proportions directed at page 290. Its action is intense, and yet superficial; 

 it plentifully raises the cuticle, yet rarely injures the true skin, and therefore 

 seldom blemishes. The application of other acrid substances is occasionally fol- 

 lowed by deeply-seated ulcerations; but a blister composed of the Spanish fly 

 alone, while it does its duty, leaves, after a few weeks have passed, scarcely a 

 trace behind. 



The art of blistering consists in cutting, or rather shaving, the hair perfectly 

 close ; then well rubbing in the ointment, for at least ten minutes ; and, after- 

 wards, and what is of the greatest consequence of all, plastering a little more of 

 the ointment lightly over the part, and leaving it. As soon as the vesicles have 

 perfectly risen, which will be in twenty or twenty-four hours, the torture of the 

 animal may be somewhat relieved by the application of olive or neat's-foot oil, 

 or any emollient ointment. 



When too extensive a blister has been employed, or, from the intensity of the 

 original inflammation, the blister has not risen, (for no two intense inflamma- 

 tions can exist in neighbouring parts at the same time,) strangury great 

 difficulty in passing mine, and even suppression of it has occurred. The care- 

 ful washing off of the blistei 1 , and the administration of plenty of warm water, 

 with opium, and bleeding if the symptoms run high, will generally remove this 

 unpleasant effect. 



An infusion of two ounces of the flies in a pint of oil of turpentine, for 

 several days, is occasionally used as a liquid blister ; and, when sufficiently 

 lowered with common oil, it is called a sweating oil, for it maintains a certain 

 degree of irritation and inflammation on the skin, yet not sufficient to blister ; 

 and thus gradually abates or removes some old or deep inflammation, or cause 

 of lameness. 



Of late cantharides have come into more general use. They were recom- 



