While we gazed at it, we observed its back to split away from the lower part of its body, and out of the gap thus formed came a soft lump which moved and writhed unceasingly.

This lump continued to increase in size until it appeared like a bunch of crab's legs: and, indeed, such it proved in a very few minutes to be; for the points of the toes were at length extricated from this hole in its back, the legs spread out, the body followed, and the crab walked away quite entire, even to the points of its nipper-claws, leaving a perfectly entire shell behind it, so that, when we looked, it seemed as though there were two complete crabs instead of one! "Well!" exclaimed Peterkin, drawing a long breath, "I've _heard_ of a man jumping out of his skin and sitting down in his skeleton in order to cool himself, but I never expected to _see_ a crab do it!" We were, in truth, much amazed at this spectacle, and the more so when we observed that the new crab was larger than the crab that it came out of.
It was also quite soft, but by next morning its skin had hardened into a good shell.

We came thus to know that crabs grow in this way, and not by the growing of their shells, as we had always thought before we saw this wonderful operation.
Now I considered well the advice which Jack had given me about preparing my tank, and the more I thought of it, the more I came to regard it as very sound and worthy of being acted on.

So I forthwith put his plan in execution, and found it to answer excellently well, indeed much beyond my expectation; for I found that after a little experience had taught me the proper proportion of sea-weed and animals to put into a certain amount of water, the tank needed no farther attendance; and, moreover, I did not require ever afterwards to renew or change the sea-water, but only to add a very little fresh water from the brook, now and then, as the other evaporated.

I therefore concluded that if I had been suddenly conveyed, along with my tank, into some region where there was no salt sea at all, my little sea and my sea-fish would have continued to thrive and to prosper notwithstanding.