Chambers's Journal of Popular Literature, Science, and Art, No. 722 / October 27, 1877

Whether the sea contains any creature at all answering to the popular idea of a 'sea-serpent'—that ophidian monster which is annually reported to have been interviewed by various crews and persons—is a problem which will only be solved by the actual capture of one of those visitors. There are, as will presently be pointed out, certain well-known true sea-snakes, the Hydrophidæ of the Indian Ocean, which swim by means of their compressed fin-like tails; but whether these marine serpents will correspond to the 'sea-serpents' of popular tales, is a matter deserving further investigation. The wide ocean presents features well suited to tempt the imagination to stray into the wildest flights. Its vastness; the difficulty of exploring even a small portion of its surface, as well as its enormous depths; its capacity for containing the strangest and most gigantic objects that fancy can picture: these are attributes of the mighty deep that have ever attracted the attention and prompted the weird imaginings of man.
It is a curious fact that recent scientific research has revealed the existence in the sea, at the greatest depths, of most minute and wonderfully formed organisms, the beauty and rarity of which necessarily secure our admiration; but instances of animals of enormous size being met with beyond those already known, are few and far between. This fact may be accounted for by the circumstance that while it is easy to construct instruments for capturing the smaller creatures living in the deep, it is a very different matter to entrap and secure an unseen monster, whose very size must endow him with enormous strength. The whale, so far as we know, is the largest denizen of the deep. Whether it is possible that it can be equalled by giants of some other order or race, is the point which public curiosity is very keen to have settled.
The appearance of great snakes at sea is recorded by more than one old voyager; but it would seem to have been only of late years that the idea of their existence has been generally confined to one, familiar to us all as the 'Great sea-serpent.'