now something of the curious internal structure of the thing operated
upon.

Regarding the Sperm Whale's head as a solid oblong, you may, on an
inclined plane, sideways divide it into two quoins,* whereof the lower
is the bony structure, forming the cranium and jaws, and the upper an
unctuous mass wholly free from bones; its broad forward end forming the
expanded vertical apparent forehead of the whale. At the middle of the
forehead horizontally subdivide this upper quoin, and then you have two
almost equal parts, which before were naturally divided by an internal
wall of a thick tendinous substance.

*Quoin is not a Euclidean term. It belongs to the pure nautical
mathematics. I know not that it has been defined before. A quoin is a
solid which differs from a wedge in having its sharp end formed by the
steep inclination of one side, instead of the mutual tapering of both
sides.

The lower subdivided part, called the junk, is one immense honeycomb
of oil, formed by the crossing and recrossing, into ten thousand
infiltrated cells, of tough elastic white fibres throughout its whole
extent. The upper part, known as the Case, may be regarded as the great
Heidelburgh Tun of the Sperm Whale. And as that famous great tierce is
mystically carved in front, so the whale's vast plaited forehead forms
innumerable strange devices for the emblematical adornment of his
wondrous tun. Moreover, as that of Heidelburgh was always replenished
with the most excellent of the wines of the Rhenish valleys, so the tun
of the whale contains by far the most precious of all his oily vintages;
namely, the highly-prized spermaceti, in its absolutely pure, limpid,
and odoriferous state. Nor is this precious substance found unalloyed
in any other part of the creature. 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
li