“I’d a good deal rather not,” said the Englishman, “I’m wiring into these books, and studying strategy; making plans for an attack upon Kronstadt.”

“Well, you take my advice, Alan, and don’t leave any of those plans round where the St. Petersburg police will find them.  Such a line of study is carried on much safer in London than here.  You’d be very welcome, Drummond, and the old boy would be glad to see you.  You don’t need to bother about evening togs—­ plain living and high thinking, you know.  I’m merely going to put on a clean collar and a new tie, as sufficient for the occasion.”

“I’d rather not go, Jack, if you don’t mind.  If I’m there you’ll all be trying to talk English or French, and so I’d feel myself rather a damper on the company.  Besides, I don’t know anything about science, and I’m trying to learn something about strategy.  What time do you expect to be back?”

“Rather early; ten or half-past.”

“Good, I’ll wait up for you.”

At five o’clock Jack was at the chemist’s and received his package.  On opening it he found the ozak in two four-ounce, glass-stoppered bottles, and these be put in his pocket.

“Will you give me three spray syringes, as large a size as you have, rubber, glass, and metal.  I’m not sure but this stuff will attack one or other of them, and I don’t want to spend the rest of my life running down to your shop.”

Getting the syringes, he jumped into his cab, and was driven to the Professor’s.

“You may call for me at ten,” he said to the cabman.

There were three others besides the Professor and himself, and they were all interested in learning the latest scientific news from New York and London.

It was a quarter past ten when the company separated.  Lermontoff stepped into his cab, and the driver went rattling up the street.  In all the talk the Prince had said nothing of his own discovery, and now when he found himself alone his mind reverted to the material in his pocket, and he was glad the cabman was galloping his horse, that he might be the sooner in his workshop.  Suddenly he noticed that they were dashing down a street which ended at the river.

“I say,” he cried to the driver, “you’ve taken the wrong turning.  This is a blind street.  There’s neither quay nor bridge down here.  Turn back.”

“I see that now,” said the driver over his shoulder.  “I’ll turn round at the end where it is wider.”

He did turn, but instead of coming up the street again, dashed through an open archway which led into the courtyard of a large building fronting the Neva.  The moment the carriage was inside, the gates clanged shut.

“Now, what in the name of Saint Peter do you mean by this?” demanded the Prince angrily.

The cabman made no reply, but from a door to the right stepped a tall, uniformed officer, who said: 

“Orders, your Highness, orders.  The isvoshtchik is not to blame.  May I beg of your Highness to accompany me inside?”