places filled.

The process of repletion and depletion is produced by the attraction of
like to like, after the manner of the universal motion. The external
elements by their attraction are always diminishing the substance of the
body: the particles of blood, too, formed out of the newly digested food,
are attracted towards kindred elements within the body and so fill up the
void. When more is taken away than flows in, then we decay; and when less,
we grow and increase.

The young of every animal has the triangles new and closely locked
together, and yet the entire frame is soft and delicate, being newly made
of marrow and nurtured on milk. These triangles are sharper than those
which enter the body from without in the shape of food, and therefore they
cut them up. But as life advances, the triangles wear out and are no
longer able to assimilate food; and at length, when the bonds which unite
the triangles of the marrow become undone, they in turn unloose the bonds
of the soul; and if the release be according to nature, she then flies away
with joy. For the death which is natural is pleasant, but that which is
caused by violence is painful.

Every one may understand the origin of diseases. They may be occasioned by
the disarrangement or disproportion of the elements out of which the body
is framed. This is the origin of many of them, but the worst of all owe
their severity to the following causes: There is a natural order in the
human frame according to which the flesh and sinews are made of blood, the
sinews out of the fibres, and the flesh out of the congealed substance
which is formed by separation from the fibres. The glutinous matter which
comes away from the sinews and the flesh, not only binds the flesh to the
bones, but nourishes the bones and waters the marrow. When these processes