The whale certainly looked very familiar every time he showed himself.
To Mr.Gibbs this lonely creature, if he were such, now became an object of intense interest.

It was evidently a specimen of the right-whale, once common in the Northern seas, skeletons of which could be seen in many museums.

Nothing would be gained to science by his capture, and Mr.
Gibbs agreed with the others that it would be a pity to harm this, the last of his race.
In thinking and talking over the matter Mr.Gibbs formed a theory which he thought would explain the presence of this solitary whale in the polar sea.

He thought it very likely that it had gotten under the ice and had pursued its northern journey very much as the Dipsey had pursued hers, and had at last emerged, as she had, into the polar sea at a place perhaps as shallow as that where the submarine vessel came out from under the ice.
"And if that's the case," said Captain Hubbell, "it is ten to one that he has not been able to get out again, and has found himself here caught just as if he was in a trap.

Fishes don't like to swim into tight places.