Varnish for Oil Paintings

1851 Scientific American  
Imagine a railway from here to the stUL How many hours is the sun frpm us 1 Why, if Power of Condensation Posse.sed by Char-we were to send a baby ill an express train, go-go from Neptune to the Sun, at the rate of fifty miles an hour, they would not have got there yet; for Neptune is more than six thousand years from the centre of ou (system. coal. ing incessantly a hundred miles an hour without Some gases are absorbed and condensed , making any stoppages, the baby would grow A Dltdnf ectlng
more » ... ent. within the pores of the charcoal, into a space to'be a boy-the boy would grow to be a man Mix four parts of dry, ground p)aster of Paseveral hundred times smaller than they b /?fore .... .. the man would grow old and die-without ris with one part of fine charcoal, by weight, occupied; and there is now no doubt they seeing the sun, for the sun is more than a hunand sow them around the premises affected the � e become fluid, or . assume a SOlid . state. dred years from us. But what is this compawith any unpleasant odor, arising from decay �s III a thousand other Ills�nces, chem i cal acred to N eptune's distance 1 Had Adam and ed animal matter, and the gases produ cing the tlOn here supplants mechamcal forces. Adhe-Eve started by our railway at the creation to odor will directly be absorbed. sion or heterogeneous attraction, as it is term-_ .: -:_c::. =-=-=--=-= -: :' ========'======== ' ==== ============== ======== ed, acquired by this dlscovery a more extended meaning; it had never bef ore been thought of as a cause of change of state in mat ter i but it is now evident that a gas adheres to the surface of a solid body by the same force which condenses it into a licluid. The smallest amount of a gas-atmospheric air for instance-can be compressed into a space a thousand times smaller by mere me chanical pressure, and then its bulk must be to the least measurable surface of a solid body, as a grain of sand to a mountain. By mere effect of mass-the force of gravity-gaseous mole cules are attracted by solids and adhere to their surfaces; and when to this physical force is added the feeblest chemical affinity, the liquefiable gases can not retain their gase ous state. The amount of air condensed by these forces upon a square inch of surface is certainly not measurable'; but when a solid body, presenting several hundred square feet of surface within the space 01 a cubic inch, is brought into a limited volume of gas, we may understand why that volume is diminished, why all gases without exception are absorbed . A cubic inch of charcoal must have,' at the lowest computation, a surface of one hundred square teet. This property of absorbing gas es varies with different kinds of charcoal; it is possessed in a higher degree by those con taining the most pores, that is, where the pores are nneT; and in a 10-\v(,. l" dPgTPA in t}u� lYl(,"r, � spongy kinds, that is where the pores are larger. Cure of Rattlesnake Bite •. A correspondent of the Baltimore Ameri can, writing from Russell county, Virginia, cites two cases, one of a negro man and the other of a boy, in which severe bites of rat tlesnakes have been cured by the free admi nistration of brandy, half a tumbler full itt a time every few minutes until a quart had been taken. We have heard eye-witnesses attest the virtue of this remedy. It is said that the liquor in such cases dorB not intoxicate.-, Washington Republic. [The above is certainly a very easy, if an effectual cure; but when young Dr. Wain wright, of this city, was bit by a rattlesnake: of which bite he died-it was stated that the use of ardent spirits hastened his death. We ne ver believed the assertion; but it is well known that the bite of the rattlesnake is not very dangerous at any time, in comparison with what it is af ter long fasting. It is pro bable that some of the simple remedies stated to have proved effective, were so only in cases where water might have been just as good. Tobacco has been stated to be good for the bite of the snake, and so has strong coif ee, olive oil, ammonia, and various other things; per sonally we have had no experience, and hope We'lIever shall, but for the sake of others it is good to present different opinions. = Size for A good sizing used by draughtsmen, after scratching or spunging paper, is composed of �oz. of white gelatine, �oz. of white soap, and �oz. of alum; the gelatine and soap are dis solved together in a qualt of warm water, and alum is added, previously reduced to powder and dissolved in a separate vessel. As soon as this solution of alum is poured into the other liq uid it becomes as white as milk; it must then be cooled and bottled for use. A thin coat of this, laid with a hair brush on the scraped part of the paper, restores its primitive size and smoothness. ------�= =�= == =>------Varnish for 011 Painting .. Dextrine 2 parts, alcohol 1 part, water 6 parts. Varnish for drawings and lithographs; --Dextrine 2 parts, alcohol half a part, wa ter :2 parts. These should be prepared pre viously with two or three coats of thin starch A NBAT FARM OOTTAGB .•• ·Fig. 1. The situation, the laying out of the grounds, the arrangement oEthe out-houses, and the'ge neral contour of the principal building, are things to which the attention of our farmers should be particularly directed. With the general advantages possesse"d by our country men, we certainly look for the future eleva tion of our race in our own land. To our far mers is principally committed this trust, and we must tell th"m that dom ... t;,. b. •• �, ,J� mestic architecture and comforts, are the sure evidences of superiority or inferiority. What do Ill �n struggle, and toil, and moil for in this world but to render home more comfortable.
doi:10.1038/scientificamerican10181851-40c fatcat:gybvs54sqfc7hjmwlfj6pj5osa