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, Pil ?" replied Cusack.

"Awfully brickish of you, Philpot." Philpot took the compliment very complacently, and the two students settled themselves one on either side of the table and waited for operations to begin.
"Wire in, old man," said Pilbury, encouragingly; "cut all the jaw, you know, and start with the experiments.