Age from childhood varies.

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LESSON XXX.

poi’son ous, likely to do great harm or injury.

sep’a rate, apart from other things.

con di’tion, state; situation.

nec’es sa ry, really needed.

dis a gree’a ble, very unpleasant.

sen’si ble, wise; knowing what is proper.

ac cus’tomed, being used to.

es pe’cial ly, more than usual.

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AIR.

We all know very well that we can not live without breathing.

What we do not all know, or do not all think of, is that we want not only air, but good air.  We are apt to take it for granted that any air will do for us; stale air, dirty air, even poisonous air.

What makes the matter worse is, that we can not help spoiling air ourselves by the very act of breathing.

If people are shut up in rooms where the bad air can not get out and the good air can not get in at all, they are sure to be made ill.

Some people in Scotland thought they would have a merry Christmas party, and invited their friends to come to a dance.

As it was very cold weather, they shut all the doors and windows tight, and then they began to dance.

It was a small room with a low ceiling, and there were thirty-six people dancing in it all night.  By the time morning came the air was so bad that it was really like poison; and very soon seven of the poor dancers were seized with a terrible fever, and two of them actually died.

The air we breathe out is different from the air we take in.  We send away some things with our breath which were not in the air when we took it in.

One of these is water.  Sometimes you can see this for yourself.  On a cold, frosty day, you know we can see the clouds of steam coming out of our mouths.  This steam is only very fine particles of water.

In warm weather we do not see the steam, but the water is there all the same; if you will breathe on a looking-glass at any time, you will make it dim and damp directly with the water that is contained in your breath.

We also breathe out animal matter, little particles of our own bodies just ready to decay.  We can not see them, but they soon give the air a close, disagreeable smell.  Good air has no smell at all.

And now I have something to say to you about the use of noses.

I dare say you can not see much use in the sense of smell.  Seeing, hearing, touching, are very needful to us, we all know; but as to smelling, that does not seem to have any particular value.

It is pleasant to smell a sweet rose or violet; and, I believe, smelling really forms a good part of what we call tasting.