472 [AseEMBLT 



It is well imderstox^ by physiologists that animals breathe for 

 ^ the purpose of supply .,g a definite amount of oxygen gas, and 

 1 hence, when the atmosp.ere breathed, is dilated, as on the moun- 

 tain top, a proportionally ^rgei- quantity must be inhaled to 

 supply the same amount oloxygeB, which would result from the 

 reception of a lesser inspiraiunof the atmosphere of the valley. 

 iVature has so configured the lungs of animals as to enable them 

 to expand and admit larger Inspiration proportionate to the in- 

 creased inspiratioHS durng ascent, a long continuance of which 

 causes an enlargement of thechest, with proportionate Increase 

 of breadth, strength, &o. 



Audubon, Wilson, and other o^jitliologists, inform us, that 

 birds of a habitually high flight, Uye larger air vessels than 

 those who float at lesser altitudes, iv^e same truths apply to 

 other animals. Thus, the broad-chestecl>iardy mountaineer en- 

 joys his peculiar strength and security frompulmonic affections, 

 rather from the altitude of his dormitory, as v/)mpared with the 

 level of the sea, than from his occupation or peculiarity of food. 

 The lungs of a bear from the mountain, as compaiad with those 

 of the valley, will be found larger, and even the Hr vessels of 

 fishes in mountain ponds are much larger than those from the 

 lowland rivers. Inhabitants of the city of Mexico, which is 

 9,000 feet above the sea, are never pulmonic, while consuuiption 

 is very prevalent in the low grounds of Mexico. I am -kell 

 aware that by judicious breeding, with a view to increase th<) 

 size of the chest of animals, th.at tliii desirable result lias been 

 to a fair degree attained, the question to which I now wish to 

 call the attention of the practical gentlemen present, is whether 

 young male animals reared at high altitudes, and consequently 

 having broad chests, do not render this property hereditary? If 

 so, the remedy is readily at hand. The fact that all cattle reared 

 on mountains have large ^hests,has not been disputed. He also, 

 in the course of his illustration of these facts, stated, lliat if we 

 ascended a hill, carrying in one hand a small balloon filled with 

 atmospheric air. and not elastic in the texture of the coating, it 

 would burst with very iuconsiderable alteration of elevation, and 

 this is to be accounted for from the lessened weight of atmosphere 

 surrounding tlie balloon and consequent expaueion of its contents. 



