PREFACE. 



The subject of the present work has occupied my attention 

 for more than a quarter of a century, and its increasing 

 prevalence in recent years has, owing to my official position, 

 impelled me to devote myself more seriously to its study. 

 " Roaring," as it is commonly termed, is the symptom of 

 a more or less grave defect in the horse's respiration, 

 which is eminently damaging to the animal's value, 

 and only too frequently to his usefulness. In the words 

 of an eminent veterinary surgeon of three-quarters of a 

 century ago, "It is a deteriorating scourge which too 

 often, for the credit of our profession, consigns the 

 counterpart of Eclipse himself to the shafts of the street 

 cab." 



The result of recent investigations into what has been 

 hitherto considered, in several respects, an obscure dis- 

 order, and one for which there was no remedy, is offered for 

 acceptance as a contribution towards the solution of the 

 mystery which surrounds the morbid condition that 



