Lesson xvi.] PRESSURE OF AIR. 87' 



he has to expect, for his blasphemous denial of so 

 wise and mighty a Being. 



Another remarkable property of air, which ought 

 to fill our hearts with thankfulness to the adorable 

 CREATOR, is its transparency : let us recollect in 

 what a dreary and disconsolate situation we should 

 be if the air were visible. What would then be 

 the use of that noble instrument the eye? Or how 

 should we discern those diversified and variegated 

 prospects of distant towns, green woods, flowery 

 meado.ws, fields of corn, 8cc. which now so often 

 give us pleasure ? Alas ! how dismal and gloomy 

 would be the reverse ! Surely our hearts must 

 overflow with gratitude to the DIVINE AUTHOR of 

 our existence, for such unbounded goodness to us 

 his creatures. 



Before we terminate this Lesson, we cannot for- 

 bear recurring to the use of the air in respiration ; 

 but shall point out one or two striking instances 

 which it furnishes of exquisite contrivance for the 

 most beneficent purposes. ' 



Animal heat is preserved enfirely by the in- 

 spiration of atmospheric air ! The lungs, which 

 imbibe the oxygen gas from the air, impart it to 

 the blood ; and the blood, in its circulation, gives 

 out the caloric to every part of the body. No- 

 thing can afford a more striking proof of creative 

 wisdom, than this provision for the preservation 

 of an equable animal temperature. By the de- 

 composition of atmospheric air, caloric is evolved, 

 and this caloric is taken up by the arterial blood, 

 without its temperature being at all raised by the 



addition, 



