Telegraph Apparatus.—Mr. Chas. Durant, of New York city, is the inventor of several improvements of a practical nature, intended to light en and facilitate the labors of telegraph operators. The present improvement relates to the relay machines, and its object is to do away with the trouble commonly e:fperienced in regulating the adjustments of the instrument. In this patent Mr. Durant, among other things, claims “ So com bining a relay machine and one or more batteries, or other electrical supply, with a telegraph instrument, that when, by the operation of the • instrument, the main telegraph circuit is opened or closed, another circuit, communicating with the same relay machine will be correspondingly opened and closed, and the attractive power developed in the relay magnet will be thereby modified. Effects of Discharges of Artillery upon Climate.— A correspondent from Missouri suggests that continued discharges of artillery induce rain storms. He cites the observations of several gentlemen who stated that during the wars of Napoleon heavy battles were uniformly followed by heavy rain storms. He suggests also that perhaps the change in climate of the Plains (referred to on page 214, current volume) along the line of the Pacfic Railroad, may be effected by the concussive effect, similar to that produced by the discharge of cannon, caused by the passage of trains over the hitherto undisturbed plains. All we can say on this matter is, that until a direct connection between atmospheric concussion and the fall of rain has been established, we must regard it as merely a conjecture. Method foe Crossing Streets.—Messrs. Adam and Nicolas Barth, of New York city, have submitted to us a plan for street crossing, which is perhaps worth consideration. It employs the principle of the elevator, with horizontal elevated rails to convey the platform from side to sid<il. Passengers step upon the platform, are raised to the proper hight, conveyed across, and let down upon the opposite side of the street. Mechanically this is perfectly practicable, and it might prove more acceptable than bridges. The plan is certainly free from some of the obj ections raised against bridges, though it might be found on trial to have some defects which the br.dgcs do not have. Oleography—This is the name given to the new art o ' fixing on paper the special forms which a drop of oil assume? when poured on water. These, forms, or patterns, vary with every sort of oil, and are exceedingly int ercJsting and beautiful. Oieography may be briefly described thus : Having obtained the oil pattern, lay on it for an instant a piece of glazed surface paper, then take it off and place it on a surface of ink or any other colored fluid in water or spirit. Now wash off any excess of color with plain water; when dry, the pattern is fixed. The paper becomes greasy where the oil is present and thus resists the action of the ink, but it is rapidly ab sorbed on the blank places.—S«p<imws Piesse. Steam Jets in BURNING Bricks.—The essential feature of this invention consists in so constructing a brick kiln that the products of combus ion from fires contained in furnac s at one end of the kiln are caused to forcibly permeate tk mass of bricks by the action of j ets of stea n or other equiva lent exhausting device situate at the opposite end of the kiln, and vice versa, the products of combustion being caused to pass through the mass from one end to the other of th.e kiln first in one direction and then in the opposite direction, thereby heating the bricks unifjrmly throughout; jets of steam are also directed into the combustion chambers and over the fuel of those fire-places which are in action for the time being, as well as into their corresponding ash-pits. Aerial Navigation.—We would call the attention of our readers to an article on “Aerial Navigation,” which appears in this number and which is the first of a series of articles to appear on this subj ect. Many practical and scientific men believe we are on the eve of new discoveri es which will render the navigation of the air practicable, notwithstanding the failures which ave hitherto attended experiments in this field. In this state of expectancy, the history of some of the most prominent events in the science of aerostation, especially those which have occurred in our own country, can not fail to be of interest.How INSTRUCTIONS Obtain Letters Patent FOR A COMPANY has been formed in Lynchburg, Va., for the purpose of establishing works for extractingcompounda from oak hark. They expect to begin operations very soon.