﻿70 PICTORIAL MISCELLANY. 



it, just enougn to make a blaze ; and having placed it upon a sauce? 

 or plate, light the wick and place a tumbler over it. The wick will 

 burn a short time, flicker, and then go entirely out. Can any one 

 tell me the reason why ? 



Henry. I think I can. The flame consumes the oxygen gas ; 

 and then, not having anything to live upon, goes out. 



M. F. Right. And what is there left in the tumbler ? 



Henry. The nitrogen. 



M. F. Right again ; otherwise called carbonic acid gas. Now 

 lift the saucer from the table and turn the whole apparatus upside 

 down, so that the saucer may be on the top of the glass, Light a 

 taper ; and, having carefully removed the saucer from the tumbler, 

 dip it into the air in the glass ; it will immediately extinguish the 

 flame. This experiment can be tried several times, and proves con- 

 clusively that the air is poisonous, because that which extinguishes 

 flame, if taken into the organs of breathing, is fatal to animal 

 life. I have known many children who, from fear or some other 

 cause, sleep with their heads under the bed-clothes in cold win- 

 ter nights. Now nothing could be more ruinous to their health. 

 They breathe, over and over again, some of the bad air which has 

 already been thrown off from their lungs, and which should be per- 

 mitted to move away. Many become ill from this practice. Warmth 

 should be secured by sufficient clothes upon your bed, but never 

 place your heads under the bedding, and breathe bad air it will 

 make your faces turn pale, your spirits low, and it may shorten your 

 lives. 



The poisonous air, or gas, which is left in the tumbler does not 

 fly off at the top when the saucer is removed it remains settled in 

 the bottom of the glass. It is heavier than common air. This ex- 

 plains why it is very apt to accumulate at the bottom of deep cellars 

 and wells, or other places which are not disturbed by draughts of 

 fresh air. In these places the gas settles down, just as it settles 

 down in the tumbler ; and if ignorant men go down thoughtlessly 

 into such places, they are very liable to be suffocated by it. Men 

 who are accustomed to such places, perform your experiment with a 

 lighted candle before risking their lives; that is, they let down a 

 lighted candle to the bottom. If the candle goes out, they know that 



