The Complete Works of Edgar Allan Poe - Edgar Allan Poe [825]
———
VELOCITY OF CANNON BALLS. — It has been found by recent experiments that a thirteen-pounder, with an ordinary charge, impels its ball five hundred and six yards in the first second, and that, by increasing the load, it will send it eight hundred and seventeen yards in the same interval.
———
MEDALS COPIED BY GALVANISM. — We spoke, in our last number, of Professor Jacobi's process for copying medals and engravings by galvanism. "The American Repertory of Arts, Sciences and Manufactures" (a very excellent periodical, whose publication has been lately commenced, at New York, by Professor J. J. Mapes) observes that several scientific gentlemen of that city have successfully repeated the experiments of Jacobi. The galvanic apparatus is very simple, and, by its aid, copper is precipitated from its solution as a sulphate, in a metallic form, upon the surface to be copied, making a perfect cast or impression. This discovery is of vast importance.
———
IMPROVEMENTS IN THE DAGUERREOTYPE. — Mr. A. S. Wolcott, of New York, has nearly revolutionized the whole process of Daguerre and brought the photogenic art to high perfection. The inventor, it is well know, could not succeed in taking likenesses from the life, and, in fact, but few objects were perfectly represented by him, unless positively white, and in broad daylight. By means of a concave mirror, in place of the ordinary lens, Mr. W. has succeeded in taking miniatures from the living subject, with absolute exactness, and in a very short space of time.
———
TRENCH'S PAPER MILL. — This is, perhaps, the most astonishing machine ever invented. By its means the common rags of the street are converted, in one process, and without leaving the mill, into a printed volume, cut into sheets and laid ready for the binder. Dr. Quin, in a late lecture upon the Mechanic Arts, at the New York Mechanics' Institute, remarked very truly concerning Mr. Trench's invention, that a person might "throw in his shirt at one end and see it come out Robinson Crusoe at the other." Mr. T. has deposited in the rooms of the Mechanics' Institute a single sheet of paper containing six copies of Town's Spelling Book. He says that he can manufacture, if necessary, a single sheet one mile in length.
———
THUNDER. — It is the opinion of M. Arago that thunder is never heard in the open sea, or in islands beyond seventy-five degrees of north latitude; and he thinks the same remark is applicable to continents. No reason is yet assigned. The opinion itself is based upon a variety of interesting researches.
———
THE COMPRESSED AIR ENGINE. — We mention in our last a suppositious invention of a Mr. Bissell, of N. J., which professed to make use of condensed air as a motive power, and spoke incredulously of the attempt. It appeared obvious that no greater power could be obtained from compressed air than was employed in its compression, minus the friction of the compressing machine. However Mr. Bissell may think of getting over this radical difficulty, (one involving a leading principle of physics) still he can have no claim to be considered an inventor; for we find that the very same thing has been attempted, some time ago, by M. Houdin, and a patent of importation granted for it in Belgium.
———
ANNUALS. — In the "Art Union, of Journal of Fine Arts," it is stated that during the seventeen years in which annuals have been published in England, seven millions of dollars have been expended upon them. A table is given which shows that the engravers come in for the largest share of the spoil. The sums paid them precisely double those paid the poor authors.