Now comes the Baling of the Case. But to comprehend it aright, you must know 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.