CHRONIC BRONCHITIS. 483 



nature. There is rarely much, if any, of the dry or moist 

 ' rhonchus,' — the hard and sonorous, or the moist and larger 

 bubbling sound ; nor is the pure ' sibilus ' or sibilant rale — the 

 whisthng and softer smaller crepitation, heard, as in the acute 

 bronchial inflammation. The sound is a modification or 

 mingling of the dry and moist higher-pitched noises, and is 

 rarely heard in the same animal of the same character or 

 quality at different examinations. 



When occurring independently of any previous inflammatory 

 condition, this state is usually very gradual in development, 

 and, when established, very persistent in character. Animals 

 suffering from it are exceedingly liable to unaccountable exa- 

 cerbations of the attendant cough, with wheezing and diffi- 

 culty of respiration ; they seem also susceptible of being acted 

 upon adversely by atmospheric changes. Although cough is 

 a tolerably constant symptom, it is rarely, and then only as an 

 adventitious circumstance, of a laryngeal character, or con- 

 nected with laryngeal irritation. 



In almost every instance of chronic bronchitis the respiration 

 is so far affected, particularly when put to rapid or rather 

 severe work, that the impediment is usually recognised — from 

 the nature of the abnormal sound — under the term of ' thick 

 wind ;' this, as already noted, has the peculiarity attending it 

 that the readiness with which it may be detected, even in the 

 same animal, varies with conditions of time and surroundings. 

 This defect is exceedingly persistent, and liable, from the 

 operation of various influences, to intensification of symptoms 

 apart from appreciable causes. 



Treatment. — Although less influenced by treatment than 

 acute bronchitis, it is nevertheless often much benefited by the 

 administration of such agents as we have recommended for 

 that form. I have found good results to follow from the em- 

 ployment of from one_ scruple to_ half a drachm each of 

 powdered camphor, myrrh, squills, digitalis, and extracf of 

 belladonna, made into a ball, and given morning and evening 

 for a week, and less frequently for a similar period. With this 

 medicine the horse does not require to be laid aside from work ; 

 nor need any change in the dietary be adopted, with the excep- 

 tion of the administration daily, with the oats, of one or two 

 fluid ounces of good linseed-oil. In some, much relief is obtained 



31—2 



