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· Vegetables severed from the earth, and the -trunks of the harder trees, timbers, &c. endure for some ages.* But the parts of the trunk are different; some trees being fistulous, as the alder, where the pith in the middle is soft, and the external part hard. but in timber trees, as the oak, the inner part, called the heart of the tree, is most durable.

The leaves, flowers, and even stalks of plants, are of small durațion; and either putrefy or resolve to dust and ashes: the roots being the more durable parts.

The bones of animals last long; as we see in charnel houses. Horns and teeth are very durable ; as appears in ivory, and the tooth of the sea-horse.

Skins, hides, and leather are also durable; as appears from the ancient manuscripts on vellum, &c. Paper also will last many ages; though it is less durable than parchment.

Bodies by passing the fire are rendered more durable ; as glass, bricks, &c. Even flesh and fruits that have felt the fire, prove more durable than when crude: not only because the fire pre

* There are certain trees, which in a very few years turn to moss, or mould, by lying buried in the ground. See Mr. Evelyn's Sylva, and the Philosophical Transaca tions.

vents putrefaction, but because when the aqueous moisture is gone, the unctuous moisture sup- . ports itself the longer.

Of all liquors, water is soonest absorbed by the air; but oil, on the contrary, exhales slowly, as appears both in the liquors themselves, and again when mixed with other bodies : for paper dipped in water, acquires some degree of transparency, but soon loses it again, and turns white, through the exhalation of the water; whereas paper dipped in oil, long remains transparent, because the oil does not exhale.

All gums are exceeding durable ; so likewise is was and honey.

But equability and inequability in the accidental circumstances of bodies have as great a share in the duration or destruction of them as things themselves: for timber, stones, &c. lying continually either in water or in air, last longer than if they were sometimes removed from the one to the other. So stones, laid in buildings with the same direction, as to the points of the compass, they had in the quarry, prove more durable than they otherwise would; and the case is the same in removing of plants.*

* Is this sufficiently verified ?


Let it be held as certain, that there is in all tangible bodies a spirit, or pneumatical substance, enveloped and included in the tangible parts; and that this spirit is the origin of all dissolution and consumption ; which are therefore to be prevented by the detention of this spirit.

This spirit is detained two ways; either by close compression and confinement, or by a kind of spontaneous residence. And this lodgment is solicited two ways; viz. if the spirit itself be not very moveable or sharp ; and again, if it be not excited by the external air to desert. So that there are two durable substances, a hard one and an oily: the first constringes the spirit, and the second in some measure appeases it ; and is less solicited by the air, for air is of the same substance with water; and fame with oil.*

And so much for the nature of durability in bodies inanimate.

The plants accounted cold, are annual, and die yearly, both in their root and stalk; as lettuce, purslane; wlieat; and all kinds of grain: yet there are some cold plants which last for three or four years; as the violet, strawberry, pimpernel, prim

* Let the justiess of these larger observations, and their importance, be thoroughly perceived.

rose, and sorrel ; but borage and bugloss, though so like when alive, differ in death; for borage is but annual; whereas bugloss lasts longer than one year.

Numerous hot plants bear age well ; as hyssop, thyme, savory, common marjoram, baulm, wormwood, germander, sage, &c. but fennel dies yearly in its stalk, and shoots again from the root: whereas basil and sweet marjoram endure age better than they do the winter; for when planted in a warm and well fenced place, they flourish above one year : and a bed of hyssop, clipt every six months, has been known to continue forty years.

Shrubs and bushes continue flourishing for sixty years, and some for twice that time. The vine may live to sixty, and be fruitful even to the last. Rosemary well secured, will likewise reach to sixty; and bear's-foot, and ivy to more than a hundred. The age of the bramble cannot be well computed; because bending to the earth, it strikes fresh roots; so that it is hard to distinguish the new shoot from the old.

Among large trees the longest lived are the oak, the holm, the ash, the elm, the beech, the plane, the fig, the lote, the olive, the wild olive, the palm, and the mulberry : some of these will last eight hundred years; and the shortest livers of them all, two hundred.

But odoriferous and resinous trees are in their matter or wood still more durable. It is true, the cypress, the fir, the pine, the box, and the juniper are shorter livers; but the cedar, assisted by the bulk of its body, nearly equals the above mentioned.

The ash, brisk and quick in its growth, lives to a hundred years or more; so likewise do the birch, the maple, and the service-tree: but the poplar, the lime, the sycamore, and the walnut are not so long lived.

The apple, the pear, the plumb, the pomegranate, the citron, the lemon, the medlar, the cornel, and the cherry-tree, may last fifty or sixty years, especially if now and then scoured of their moss, which surrounds some of them.

In general, largeness of bulk in trees, where other things are equal, has some affinity with their continuance of life; so likewise lias hardness of substance, and such as bear mast and nuts are generally longer lived than fruit-trees. So again, those that are late, either in fruit or leaf, and also shed late, are longer lived than such as bear and shed early : so wild trees are longer lived than those of the orchard, and of the same kind such as bear an acid fruit live longer than such as bear a sweet one.

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