branch with no real
fork or living bough to divide it or diminish it, the tapering is
scarcely to be detected by the eye; and if we select a portion without
such evidences of past ramification, there will be found none
whatsoever.

Sec. 4. And care of nature to conceal the parallelism.

But nature takes great care and pains to conceal this uniformity in her
boughs. They are perpetually parting with little sprays here and there,
which steal away their substance cautiously, and where the eye does not
perceive the theft, until, a little way above, it feels the loss; and in
the upper parts of the tree, the ramifications take place so constantly
and delicately, that the effect upon the eye is precisely the same as if
the boughs actually tapered, except here and there, where some
avaricious one, greedy of substance, runs on for two or three yards
without parting with anything, and becomes ungraceful in so doing.

Sec. 5. The degree of tapering which may be represented as continuous.

Hence we see that although boughs may, and must be represented as
actually tapering, they must only be so when they are sending off
foliage and sprays, and when they are at such a distance that the
particular forks and divisions cannot be evident to the eye; and
farther, even in such circumstances the tapering never can be sudden or
rapid. No bough ever, with appearance of smooth tapering, loses more
than one tenth of its diameter in a length of ten diameters. Any greater
diminution than this must be accounted for by visible ramification, and
must take place by steps, at each fork.

Sec. 6. The trees of Gaspar Poussin;

And therefore we see at once that the stem of Gaspar Poussin's tall
tree, on the right of the La Riccia, in the National Gallery, is a
painting of a carrot or a parsnip, not of the trunk of a tree. For,
being so near that every individual leaf is visible, we should not have
seen, in nature, one branch or stem actually tapering. We should have
received an _impression_ of graceful diminution; but we should have been
able, on examination, to trace it joint by joint, fork by fork, into the
thousand minor supports of the leaves. Gaspar Poussin's stem, on the
contrary, only sends off four or five minor branches altogether, and
both it and they taper violently, and without showing why or
wherefore--without parting with a single twig--without showing one
vestige of roughness or excrescence--and leaving, therefore, their
unfo