nd Franz, who alone was in the secret.

'All right!' answered Franz; 'I will send you three telegrams, and catch
you three swallow-tails too if I can manage it.'

As he went out of the room, his school-fellow looked wistfully at the
pair of crutches that stood beside his invalid's chair. He was the only
son of a very rich German nobleman, and six months before he had been
nearly killed in a railway accident. When he began to recover, the Baron
had promised to give a special treat to his son's class in honour of
the event, and now that the time for the annual excursion had arrived,
he was paying all expenses for the boys to remain three days in the
forest instead of, as was usual, only one. It is the custom in German
schools for each master to take his class for a long day's expedition
into the country during the summer, in which he is supposed to open
their eyes to the beauties of nature and the wonders of the botanical
world; and the Baron, who was a very wealthy man, had caused this
privilege to be extended that year. But now his son was unable to enjoy
it, and this use of telegrams was a suggestion of his father's to
prevent his being too depressed by the thought of his disappointment.

[Illustration: "He looked wistfully at the pair of crutches."]

* * * * *

At five o'clock on the following morning there was a very cheerful party
of boys waiting at the station for the little hill-climbing train that
was to take them into the heart of the Black Forest. The master, Herr
Groos, was also in the best of spirits, in spite of his failure to make
any of the boys listen while he explained to them how the train was
enabled to climb a hill. The boys, with their yellow caps, which was the
distinctive colour of their class, and their butterfly-nets, botanical
presses, and green specimen-cases, were much too excited to listen to
him.

At last the train arrived, and they all filed into an open third-class
carriage, whose only other occupants were two strangers, a tall and a
short one, also armed with butterfly-nets and enormous green cases.

'Did you see Hugo yesterday?' inquired Herr Groos of Franz, who was
sitting next him.

'Yes, sir; I was there a long time. He wished he was coming with us.'

'Well, we all wish it too,' said the master heartily. 'What does he do
with himself all day? Invent more cyphers?'

'No, sir, he does not mean to invent a new one,' answered Franz,
laughing, 'til