Delicate

Though in life it remains perfectly fluid, yet, upon exposure to the air, after death, it soon begins to concrete; sending forth beautiful crystalline shoots, as when the first thin delicate ice is just forming in water. A large whale’s case generally yields about five hundred gallons of sperm, though from unavoidable circumstances, considerable of it is spilled, leaks, and dribbles away, or is otherwise irrevocably lost in the ticklish business of securing what you can.

I know not with what fine and costly material the Heidelburgh Tun was coated within, but in superlative richness that coating could not possibly have compared with the silken pearl-coloured membrane, like the lining of a fine pelisse, forming the inner surface of the Sperm Whale’s case.