The branches had been trimmed away here and there, so that a good view could be had of what was happening elsewhere in the orchard.  A scream of surprise and delight came from the group, in which Olive joined.  Quickly as the children scrambled into the tree, the Doctor was up there first, laughing and saying that it was thirty years since he had climbed that apple tree; for after he went away to college the old seats had decayed and fallen down.

“Give me your hand and I’ll help you up,” called Nat to Rap, who had dropped his crutch and was looking up at the others.

“No, you needn’t,” said Rap.  “I can climb all right.  Sometimes it isn’t so handy for me, but other times it’s easier, for in tight places one leg doesn’t take up as much room as two;” and he swung and pushed until he was up as high as the rest.

“Here’s a nest with eggs in it,” whispered Dodo, who had crept out on a limb, where a rather large round nest, made of grass and little sticks plastered together with mud, was saddled on the branch—­in fact, a Robin’s nest.

“Four lovely smooth eggs, not quite blue and not quite green!  Please, can I have them?  I saw them first.”

“Think a minute, Dodo,” said the Doctor.  “A bird will come from each of those eggs.  Suppose you take the eggs away from the poor Robins, you will be killing four young birds, besides hurting the feelings of their parents and making them leave the orchard, very likely.  You must not take any eggs in the nesting season—­not even one.  I will tell you what happened once in a field where there were some birds’ nests in the bushes.

“The man who owned the field was fond of birds and wished to protect them, but he was so good-natured that when his little boy came to him and said, ‘I wish so much to have some birds’ eggs—­all the boys collect them—­please let me take a few, father—­only on our own land,’ he did not wish to say ‘No.’  Sometimes, to be good-natured is as bad as to be cruel.  This man said, ’You may take one egg from each nest, but only one, remember.’  So the boy went out and took a few eggs, but then he carried them to school, showed them to the other boys, and told them where they came from.  Then each boy said to himself, ’It will be all right if I take only one egg from each nest.’  But when four or five boys had each taken one, all the nests were quite empty.  So the poor birds left that man’s field, where the bugs and worms grew and throve, till they ate up his hay and all the rest of his crops.

“When the nesting season is over eggs that have not hatched are often left in the various nests, that you can take without doing any harm.  Of course I know it is not easy to keep your hands off such pretty things as birds’ eggs; but if by doing so you can be patriotic and useful, it is an act of self-denial that you will be glad to do for the good of the country.”

“What is in that black case, uncle?” asked Dodo.  “Is it a pistol to shoot birds?  I think it looks too fat for that.”