equired great judgment
and caution, and it had been a subject of very careful consideration by
Roland Clewe.

When he had returned to Cape Tariff, after parting with the Dipsey, he
had received several messages from Sammy, which assured him that the
submarine voyage was proceeding satisfactorily. But when he went on
board the Go Lightly and started homeward, he would be able to hear
nothing more from the submarine voyagers until he reached St. John's,
Newfoundland--the first place at which his vessel would touch. Of
course constant communication with Sardis would be kept up, but this
communication might be the source of great danger to the plans of Roland
Clewe. Whatever messages of importance came from the depths of the
arctic regions he wished to come only to him or to Mrs. Raleigh. He had
contrived a telegraphic cipher, known only to Mrs. Raleigh, Sammy,
and two officers of the Dipsey, and, to insure secrecy, Sammy had been
strictly enjoined to send no information in any other way than in this
cipher.

For years there had been men, both in America and in Europe, who had
been watching with jealous scrutiny the inventions and researches of
Roland Clewe, and he well understood that if they should discover his
processes and plans before they were brought to successful completion he
must expect to be robbed of many of the results of his labors. The first
news that came to him on his recent return to America had been the tale
told by Sammy Block, of the man in the air who had been endeavoring to
peer down into his lens-house, and he had heard of other attempts of
this kind. Therefore it was that the telegraphic instrument on the
Dipsey had been given into the sole charge of Samuel Block, who had
become a very capable operator, and who could be relied upon to send
no news over his wire which could give serviceable information to the
operators along the line from Cape Tariff to Sardis, New Jersey.

But Clewe did not in the least desire that Margaret Raleigh should be
kept waiting until he came back from the arctic regions for news from
the expedition, which she as well as himself had sent out into the
unknown North. Consequently Samuel Block had been told that he might
communicate with Mrs. Raleigh as soon and as often as he pleased,
remembering always to be careful never to send any word which might
reveal anything to the detriment of his employers. When a message should
be received on board the Dipsey that Mr. Clewe was