356 PHYSIOLOGY AND HEALTH. 



school-rooms are usually furnished with seats of one kind, 

 and nearly of one size, and made without regard to the hu- 

 man shape. These seats are sometimes without backs, and 

 sometimes with backs so square and perpendicular as to give 

 no comfortable support. They are often so high that the 

 smaller boys find no rest for the foot, or so low that the 

 larger boys have not the usual support for the thigh. They 

 are often built on an inclined plane, upon which the foot 

 tends to slide forward and downward, and the child is then 

 continually reminded of his position by his uncomfortable 

 feelings, and is compelled to make constant exertion "of his 

 muscles to prevent his feet sliding forward. 



820. Some school-houses are so situated as to be pro- 

 tected neither from the severest storms of winter nor from the 

 burning sun of summer. They are often imperfectly warmed, 

 and the temperature is unequal in the various parts. There 

 are many whose chilly feet, in the cold season, make irresisti- 

 ble drafts^upon their attention; and, in the warm season, in 

 the absence of both shade-trees and blinds, or curtains, the 

 heat and the glare of the sun make equal claims upon their 

 feelings, and withdraw their attention from their books. It 

 is all in vain that their teachers urge upon them to study 

 vigorously, and forget their discomforts, and that the good 

 scholar, who is anxious for his lessons, does not regard these 

 external matters. The physical sensations will come first; 

 they will have the first care of the brain and the mind; and 

 it is only by great mental discipline such as few children 

 possess that they can be resisted and forgotten. And what- 

 ever attention these suffering children give to the physical 

 sensations is manifestly not given to their lessons. 



821. The same incompatibility exists between great fa- 

 tigue and mental labor. While the nervous energies are 

 devoted to restoring power to the muscles, they cannot be 

 given to thought or reflection. The boy who is wearied 

 with hard work before the hours of school, has not then the 

 free command of his brain for his mental action. Very la- 

 borious men are apt to fall asleep when they take up a book, 



