400 ^4 Man /'a/ of Veterinary Physiology. 



impressed the writer with the propriety of drawing the 

 following comparison between the ages of horses and men : 



' The first five years of a horse may be considered as 

 equivalent to the first twenty years of a man ; or thus, a 

 horse of five years may be comn/paratively considered as old 

 as a man of twenty ; a horse of ten years as a man of forty ; 

 a horse of fifteen as a man of fifty ; a horse of twenty as a 

 man of sixty ; of twenty-five as a man of seventy ; of thirty 

 as a man of eighty ; and of thirty-five as a man of ninety. 



' So far from this comparison being too much in favour of 

 the horse, we are disposed to think it too little so. 



' Horses of thirty-five years of age are as common as men 

 of ninety, provided it be taken into account there are at 

 least fifty human subjects for every horse ; and, unquestion- 

 ably, a horse of forty-five is less rare than a man of a 

 hundred and ten.' 



Death. — Death from natural causes in the horse is a 

 matter of rare occurrence ; it is seldom that an animal is 

 taken such care of that the tissues are worn out by age and 

 decay, and the breath of life passes gradually from the b< >dy : 

 by far the majority of horses meet either with a violent 

 death or one the result of disease. 



Natural death is described as commencing either at the 

 heart, lungs, brain, or blood. Probably in the main most 

 cases of natural death may be attributed to a failure of the 

 heart's action ; but from what we know of the physiology of 

 the heart, respiration, and blood, it is very difficult to separate 

 these in discussing the causes of natural death, knowing as 

 we do how completely one is dependent on the other. The 

 cessation of the heart's action may be looked upon as the 

 termination of life. 



We cannot enter upon the causes of death the result o\' 

 disease, excepting to notice the interesting fact that no 

 matter what the cause of death may be, horses seldom die 

 quietly ; by far the majority of them leave this world 

 in powerful convulsions, lighting or struggling to the last, 

 lying on their side, and galloping themselves to death. 

 Rarely, indeed, does one witness a quiet death in horses, 



