The cobweb-like spawn frequently observed about the roots of trees, especially of evergreens recently set out, should receive immediate attention whenever detected. The remedy to adopt if a plant appears in an unhealthy state (if in pots or planted out), is to take it up, being careful to preserve all the roots, and shake off every particle of soil from them, wash the roots, shaking and dipping them in water several times until they appear quite clean. Transplant either into the open ground, or into a wide, flat basket, have the roots disentangled, and laid out regularly. In spring, or early in the autumn, is the best time for performing this operation. In many cases in which Conifers are grown, and annually shifted into larger pots, probably for some four or five years, the roots become entangled and twisted into eaoh other, and they are often planted out in that state, only loosening a few of the bottom ones; this kind of treatment, in a few years, must prove injurious, if it does not in time kill the plant. Coniferae are often raised and grown in pots for a long time, sent to America, and afterwards planted out in the open ground with the roots matted together, and the ball entire.

In such cases, the soil should be shaken from the roots, and untwisted up to the stem, and regularly laid out. A stake is necessary for a year or two, to keep the plant steady.

Frasenius, a German chemist, has made experiments on various fruits, demonstrating which are best, and why. The more a fruit contains of soluble matter, the more it is esteemed - such as the peach and greengage. And the more a fruit is cultivated, the more does it contain of sugar, and the less of free acid and soluble matter. These facta may serve for household hints.

Rudolph Wagner has recently shown that a solution of decomposed salicilate of potash yields a liquor strongly charged with the scent of roses; and if this be distilled, it becomes an excellent artificial rose-water. Out of this a new branch of industry may be created, for the substance is comparatively cheap, and rose-water is much in request as a luxury for the toilet, &C.

A new kind of gutta percha, and, it is said, the best, has been imported into Holland from Surinam. It is a product of a species of sapodilla, which grows in such abundance, that, for years to come, the supply will be equal to the demand.

We shall shortly give a drawing of a stove for heating greenhouses by gas; it is now used abroad with manifest advantage, as it admits of regulation with nicety to any degree of temperature. Gas is now stated to be a preventive of contagion; for, according to accounts from Lisbon, the yellow fever did not visit the houses in that city which are lighted with gas.

Professor Cook stated, at the last meeting of the American Association for the Advancement of Science, that a subsidence is going on all along the coast from Delaware Bay to Boston. In New Jersey and Long Island, the effects are especially observable. Hundreds of thousands of acres of submerged forest lie a few feet below the swampy surface, and many farms have diminished within the memory of man. The Professor estimates the subsidence at two feet in a century. Two thousand years ago, Ovid sang:

"The face of places and their form* decay, And that is solid earth which once was sea; Seas, in their turn, retreating from the shore, Hake solid land what ocean was before; And far from strands are shells of fishes found, And rusty anchors fixed on mountain ground; And what were fields before, now washed and worn By falling floods, from heights to valleys turn".