VENTILATION OF STABLES. 49 



whether the disease arise merely from a deficient supply of 

 oxytjen, or from some peculiar poison generated during res- 

 piration and perspiration, can not be positively known. 

 Chyinists, indeed, deny the existence of this animal poison. 

 They can not find it ; hut it does not, therefore, follow that 

 there is none. To their tests the matter of glanders and 

 that of strangles appear to be perfectly similar. That they 

 are not the same, however, is proved by applying them to a 

 living being. The air may contain a poison which no test 

 merely chyniical can detect. 



The EoHs of an Impure At7nosphere, vary according to 

 several circumstances. The ammoniacal vapor is injurious 

 to the eyes, to the nostrils, and the throat. Stables that are 

 both close and filthy, are notorious for producing blindness, 

 coughs, and indammation of the nostrils ; these arise from 

 acrid vapors alone. They are most common in those dirty 

 hovels where the dung and the urine are allowed to accumu- 

 late for weeks too^ether. The air of a stable may be con- 

 taminated by union with ammoniacal vapor, and yet be 

 tolerably pure in other respects. It may never be greatly de- 

 ficient in oxygen : but when the stable is so close that the 

 supply of oxygen is deficient, other evils are added to those 

 arising from acrid vapors. Disease, in a visible form, may 

 not be the immediate result. The horses may perform their 

 work and take their food, but they do not look well, and they 

 have not the vigor of robust health. Some are lean, hide- 

 bound, having a dead dry coat ; some have swelled legs, 

 some mange, and some grease. All are spiritless, lazy at 

 work, and soon fatigued. They may have the best of food, 

 and plenty of it, and their work may not be very laborious ; 

 yet they always look as if half-starved, or shamefully over- 

 wrought. When the influenza comes among them, it spreads 

 fast, and is difiicult to treat. Every now and then one or two 

 of the horses becomes glandered and farcied. 



Stables are close in various degrees, and it is only in the 

 closest that their worst evils are experienced. But bad air 

 is most pernicious when the horses stand long in the stable, 

 when the food is bad, and when the work is laborious. 

 Hence it is chiefly in the stables occupied by coaching and 

 boat-horses, that the effects of a foul atmosphere are most de- 

 cisively announced. Other stables, such as those used for 

 carriage-horses, hunters, racers, and roadsters, may be equally 

 ill-ventilated ; yet the evils are not so visible, nor of the 

 same kind ; coughs, inflamed lungs, a marked liability to ia- 



5 



