William said he thought they would not.  If the chestnuts were good, he was afraid they would pick them off and eat them if they were small.

All the rest of the boys in the school thought so too.

“Here, then,” said the master, “is one reason for having prickles around the chestnuts when they are small.  But then it is not necessary to have all chestnuts guarded from boys in this way; a great many of the trees are in the woods, which the boys do not see; what good do the burrs do in these trees?”

The boys hesitated.  Presently the boy who had the green satchel under the tree with Roger, who was sitting in one corner of the room, said,

“I should think they would keep the squirrels from eating them.

“And besides,” continued he, after thinking a moment, “I should suppose, if the meat of the chestnut had no covering, the rain would wet it and make it rot, or the sun might dry and wither it.”

“Yes,” said the master, “these are very good reasons why the nut should be carefully guarded.  First the meats are packed away in a hard brown shell, which the water can not get through; this keeps it dry, and away from dust and other things which might injure it.  Then several nuts thus protected grow closely together inside this green, prickly covering, which spreads over them and guards them from the larger animals and the boys.  Where the chestnut gets its full growth and is ripe, this covering, you know, splits open, and the nuts drop out, and then any body can get them and eat them.”

The boys were then all satisfied that it was better that chestnuts should grow in burrs.

“But why,” asked one of the boys, “do not apples grow so?”

“Can any body answer that question?” asked the master.

The boy with the green satchel said that apples had a smooth, tight skin, which kept out the wet, but he did not see how they were guarded from animals.

The master said it was by their taste.  “They are hard and sour before they are full grown, and so the taste is not pleasant, and nobody wishes to eat them, except sometimes a few foolish boys, and these are punished by being made sick.  When the apples are full grown, they change from sour to sweet, and become mellow—­then they can be eaten.  Can you tell me of any other fruits which are preserved in this way?”

One boy answered, “Strawberries and blackberries;” and another said, “Peaches and pears.”

Another boy asked why the peach-stone was not outside the peach, so as to keep it from being eaten; but the master said that he would explain this another time.  Then he dismissed the scholars, after asking Roger to wait until the rest had gone, as he wished to see him alone.

Several of the articles which follow were communicated for this work by different teachers, at the request of the author.

11.  THE SERIES OF WRITING LESSONS.—­Very many pupils soon become weary of the dull and monotonous business of writing, unless some plans are devised to give interest and variety to the exercise; and, on this account, this branch of education, in which improvement may be most rapid, is often the last and most tedious to be acquired.