Willoughby; that is,
he assisted the boy who assisted the chemistry fag who assisted the
assistant master to the science master; and _on_ the strength of this
distinction he was allowed some special privileges in the way of
improving himself in his favourite branch of study. He was on the whole
rather a promising pupil, and had a very fair idea of the properties of
the several substances he was allowed to experiment with. Indeed he had
had to pass an examination and perform some experiments in the presence
of the master before he was allowed to enter the laboratory as a private
student at all. No one knew exactly how he distinguished himself on
that occasion, or how he succeeded with his experiments, but it was
well-known that, if he had succeeded then, he had never done so since;
that is, according to anybody's idea but his own.

Cusack and Pilbury found him busy blowing through a tube into a bottle
of water, looking very like a purple cherub bursting at the cheeks. He
was so engrossed with his task that he did not even notice their entry,
indeed it was not till Pilbury had stepped behind him and clapped him
suddenly on either side of the face, making his cheeks explode like a
small balloon, and spilling the contents of his bottle all over the
table, that he became aware that he had visitors. "What a frightful
idiot you are, Pilbury!" he exclaimed; "you've spoilt that whole
experiment. I wish you'd shut up fooling and get out."

"Awfully sorry, old man," said Pilbury, "but you did look so jolly
puffed out, you know; didn't he, Cusack?"

"Now you've done, you'd better hook it," said Philpot, "you've not got
leave to come here."

"Oh, don't be riled," said Cusack; "the fact is, Pil and I came to see
if you'd put us up to a thing or two in this sort of business."

"We've gone on the steady, Phil, you know," explained Pilbury, in
conciliatory tones, "and thought it would be rather jolly if we three
worked up a little chemistry together."

"We'd watch you do the things at first, of course," said Cusack, "till
we twigged all the dodges."

"And it would be jolly good practice for you, you know, in case ever old
Mix-'em-up is laid up, and you have to lecture instead."

Philpot regarded his two would-be pupils doubtfully, but softened
considerably as they went on.

"You'll have to promise not to fool," said he, presently, "or there'll
be a row."

"Oh, rather; we won't touch anything without asking, will we, P