POINTS IN MANAGEMENT. 97 



In direct connection with this is the subject of ventila- 

 tion. The assimilative and formative process is sensibly 

 affected by it. As I have stated, the food taken by the 

 animal is elaborated into the ' organism ' through the 

 blood, and this is effected through the instrumentality of 

 the oxidation of the blood. The oxygen of the atmo- 

 sphere being inhaled into the lungs, comes into contact 

 with the blood, and is taken up by it, effecting a combus- 

 tion of the hydro-carbons of the food, by means of which 

 animal heat is generated, as before said ; and through its 

 agency the machinery of elaboration (the manufacture of 

 flesh, fat, &c.) is kept in operation. Stop the supply of 

 oxygen, and the fire goes out and the machinery ceases to 

 work. Diminish the supply of oxygen, and cause this di- 

 minished supply to enter into the lungs, associated with 

 deadly and noxious vapours, and the work is imperfectly 

 performed, and disease and wasting ensue. 



The vapours generated in a close shed or house in 

 which animals are kept are carbonic acid gas, sulphurated 

 hydrogen, and ammoniacal vapours, which have the effect 

 of thinning the blood and paralysing its circulation ; 

 while the deficiency of oxygen causes to be left unburned 

 in the blood fatty globules, which obstruct the circulation, 

 and to a certain extent poison, as it were, the system, by 

 clogging it with unassimilated matter and depriving it of 

 all tone or vigour of life, which constitutes health and 

 development. 



The want of cleanliness, as well as of fresh air, with its 

 life-spring of oxygen, is of very serious prejudice to 

 health. I may here call attention to the very grave evil 

 which appears to have taken chronic possession of many 

 flocks from which the ' galpon ' the shedded sheep of 

 many, if not most, of our first-class sheep-breeders are 

 never free, viz. the scab ; and more especially those of 



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