190 , BOARD OP AGRICULTURE. , [Jan., 



its life would cease to exist. Pure air is its life ; a vitiated air is 

 akin to no air at all, therefore akin to death. How necessary, then, 

 for us to study the subject thoroughly, for during a long period of 

 the year the severity of our climate compels us to house our ani- 

 mals, not only to secure their comfort, but for the convenience of 

 feeding and giving suitable care, and most essentially from a point 

 of economy. 



Where stock roam at large almost in a condition of nature, and 

 where farm buildings are a series of half-open sheds, and on many 

 of our New England farms, where barns have more the appearance 

 of bird-cages, so wide are the cracks between the boards, an in- 

 quiry like ours would be unwarrantable, for ventilation is pos- 

 sessed to an extreme degree, and the contrary question of shutting 

 off the supply of air would be more pertinent to the farmer's mind 

 and pocket. But agriculture is rapidly advancmg. The capabilities 

 of our land and stock are being everywhere demonstrated. A 

 more careful and saving system is coming into vogue. Better 

 buildings are one of the leading essentials of this new system, and 

 in these new buildings we cause our stock to lead more artificial 

 lives, because we find therein more profit. It is not our desire to 

 make their lives artificial; circumstances compel us to do so, our 

 aim being to make them as natural as possible. 



To the full understanding of this question we must study the 

 first requisite of a natural life — a pure, unvitiated atmosphere. 

 Of what does this consist, and what influence does it exert upon 

 animal life ? 



Our earth is surrounded by an atmosphere of air, supposed to 

 be at least forty-five miles in height, and perhaps much farther 

 than this, but in an extremely attenuated condition. One hundred 

 cubic inches of it weigh at the mean temperature and pressure 

 very nearly thirty-one grains. It presses upon the earth at the 

 level of the sea with a weight equal in round numbers to fifteen 

 pounds upon every square inch of surface. Owing to physical 

 causes it is ever in motion, either as a gentle breeze, a swift wind, 

 or the destructive and terrible tornado. Although invisible to us, 

 it is so famihar as to be regarded with but little curiosity or atten- 

 tion ; yet in it we find the means of life. The ancients classed it as 

 one of the four great principles of nature — earth, fire, water, and 

 air ; we have learned to look for subdivisions, and we find that air 



