VENTILATION. 185 



shape*'of a mere scientific discussion ; and that some who 

 have been in the habit of considering all air, except in the 

 particular of temperature, as about alike, may be thoroughly 

 convinced of their mistake. 



Kecent statistics prove that consumption and its kindred 

 diseases are most fearfully on the increase, in the Northern, 

 and more especially in the New England States ; and that 

 the general mortality of Massachusetts exceeds that of al- 

 most every other state in the Union. In these States, the ten- 

 dency of increasing attention to manufacturing and mechani- 

 cal pursuits, is to compel a larger and larger proportion of the 

 population to lead an in-door life, and to breathe an atmosphere 

 more or less vitiated, and thus unfit for the full development of 

 vigorous health. The importance of pure air can hardly be 

 over-estimated ; indeed, the quality of the air we breath, 

 seems to exert an influence much more powerful, and hard- 

 ly less direct, than the mere quality of our food. Those 

 who, by active exercise in the open air, keep their lungs 

 saturated as it were, with the pure element, can eat almost 

 anything with impunity ; while those who breath the sorry 

 apology for air which is to be found in so many habita- 

 tions, although they may live upon the most nutritious 

 diet, and avoid the least excess, are incessantly troubled 

 with head-ache, dyspepsia, and various mental as well as 

 physical sufferings. Well may such persons, as they wit- 

 ness the healthy forms and happy faces of so many of the 

 hardy sons of toil, exclaim with the old Latin poet, 

 " Oh dura messorum illia !" 



It is with the human family very much as it is with the 

 vegetable kingdom. Take a plant or tree, and shut it out 

 from the pure. air, and the invigorating light, and though you 

 may supply it with an abundance of water and the very soil, 

 which by the strictest chemical analysis, is found to contain 



