[Nothing can compensate for want of rapidity in a language designed for colloquy. Although our correspondent found the Morse telegraph alphabet a resource on occasion, he would scarcely be content to use it, and it only for life, even if emancipation from it involved months of labor. The motions required to spell SCIENTIFIC AMERICAN by the telegraph alphabet are thirty-nine, but as the short dashes occupy the time of two dots for each dash, and there are eight of these, eight more ought to be counted in a comparison of it with an alphabet composed wholly of dots, this would make forty-seven. To spell the same words in full by the mute alphabet referred to would require only twenty-three motions. A still greater disparity in rate would, we think, be found in an entire colloquial sentence. Thus the sentence "Hand me an apple" would require, by the mute alphabet, the time of fourteen dots, while with the telegraph alphabet it would require the time of thirty-nine.--Eds.] * * * * * Cheap Cotton Press Wanted. Messrs. Munn & Co.:--Please give us any information of cheap cotton-presses, such as small neighborhoods, or single planters, in the South could own. In particular, a press that will put 40 pounds cotton into each cubic foot. We want cotton better handled, and to that end may want small bales, say 150 pounds each. But these must be put into three or four cubic feet, or they will cost too much for covering, ties, etc. Perhaps you can furnish us with a wood-cut of some, or several, presses worked by hand, or by horse-power, that will do good service, not cost too much, be simple in operation, not require too much power, and be effective as above. It may be for the interest of some of your clients or correspondents to give us the facts, as we shall put them into a report for circulation amongst the entire cotton interest of the country. Yours very truly, WALTER WELLS, _Sec'y_. National Association of Cotton Manufacturers and Planters, No. 11, Pemberton Square, Boston, Mass. * * * * * A Singular Freak of a Magnet. Messrs. Editors:--In my library hangs a powerful horseshoe magnet which has a keeper and a weight attached of about three ounces. This weight is sustained firmly by the attracting power of the magnet, and is not easily shaken off by any oscillating motion, yet through some (to me) unknown cause during each of the last ten nights the magnet has lost its power, and the keeper and weight lie in the morning on the bottom of the case where the magnet has hung for many years without a like occurrence, except once on the occasion of a severe shock of an earthquake which took place December 17, 1867. There is no possible way for this magnet to be disturbed except by the electric current; then why should its power thus return without the aid of a battery or keeper? Will some one explain? FLOYD HAMBLIN. Madrid Springs, N.Y. * * * * *