411 



CHAPTER XV. 



383. What effect has corrupted air on a crowded audience ? 



384. What effect has an ill- ventilated school-room on the children? 

 385 What occurred in the Black-hole of Calcutta ? What is the dif- 

 ference between this result and the faintness of a crowded room? 



386. What effect has pure carbonic acid gas ? 



387. What is a common source of danger from carbonic acid gas? 



388. How does drowning produce death? 



389. What are some more remote effects of bad air? 



390. Why are females more susceptible of consumption than males 7 



CHAPTER XVI. 



391. How does the privation of air affect different animals! 



392. What power can man acquire by long practice ? 



393. What necessity is imposed on all animals ? 



394. 395. Is there any natural deficiency of air? 



396. What reciprocal offices do animals and vegetables perform ? 



397. When do vegetables consume carbonic acid ? When give it 

 out? 



398. When are house-plants salutary ? When injurious ? 



PART IV. , 



ANIMAL HEAT. 



CHAPTER I. 



399. What is the temperature of most animals compared with that 

 of the surrounding medium ? 400,401. What illustrations? 



402. What were the experiments of Sir Charles Blagden ? 



403. What tendency is almost universal? 404. Illustrate. 



405. What exception to this tendency ? 



406. What effects would follow, if living bodies could not retain a 

 uniform temperature ? 



CHAPTER II. 



407. How is the heat of the living body affected by cold bodies? 



408. How does the law of heat among dead substances differ from 

 this? 



409. What is the origin of the heat in living bodies ? 



410. Into what classes are animals divided in relation to heat? 



411. From what difference of structure does this difference of tem- 

 perature arise ? 



412. Does the same distinction occur among the inhabitants of the 

 sea ? 



413 What conditions are necessary to maintain this internal heat! 



