Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 4, 1802).djvu/469

433&#93; INS in an oblong six-sided prism : it maybe taken off at pleasure, by a ring conneAed with the top. — The whole of this fabric has the singular advantage of throwing a great body of light on the plants, while it prevents that sickly growth, denominated etiolation; and ren- ders it easy to produce a variety of temperatures, as occasion may re- quire, M. Benard's hot-house is supplied with heat, at a trifling ex- pence, by common oil ; the smoke of which is conveyed round the frame, by means of a flue. HYACINTH.— In a late volume of the " ^finales de Chimie," M. I R O [433 Leroux has announced the disco- very of a gummy substance, con- tained in the roots of the Hyaciri' thus von-scriptus ; which is an indigenous vegetable. This sub- stance appeared, on examination, to possess similar properties with the generality of gums, and a con- siderable portion of farinaceous matter ; which may, by proper ma- nagement, be extracted. As it abounds in the bulbous roots of the Hyacinth, so as to render it an ob- je6l of attention, M. Leroux con- ceives that it might be advantage- ously converted into Starch. I. INSECTS.— A new mode of preventing their depredations on apple-trees, has lately been pro- posed in America. It consists simply in stripping off the whole body of the bark ; an operation by which millions of insefts, together with their eggs, are immediately removed. Such praftice, indeed, has generally been supposed to kill the trees ; but it appears, from the experiments instituted by Dr. MiTCHiLL, of New- York, that about Midsummer, apple - trees may be entirely decorticated, with- out receiving the least injury from the operation/ Thus, a tree peeled in the summer of 1798, withstood the effefts of intense frost in the severe winter that succeeded ; ano- ther, which had been deprived of its bark in June, 1799, re-acquired it completely before the end of September; and yielded as large a crop of fruit, as if it had not been <li vested of its rind. — Dr. Mitch- jsrc, XVI. — VOt. IV. ILL observes, " There is no doubt, an orchard might be treated in this manner with perfeft safety, if the operation were well-timed ;" and, as the climate of North America is considerably colder than that of England, these experiments claim the attention of British Or- chardists. IRON. — As vessels, made of this metal, are liable to cracks, which frequently render them useless, we insert, on the authority of M. Kas- TELEYN, the following dire6tions for preparing a lute calculated to fill up such fissures : — ^Take six parts of yellow potter's clay, and one part of iron filings ; incorpo- rate these ingredients with a sutli- cient quantity of Unseed oil, so as to form the whole into a paste o£ the consistence of putty. Although a variety of varnishes have been contrived for securing iron and steel, in a polished state, from the efl:efts of rust ; yet we F f are