A correspondent who is well qualified to judge of such matters, sends us an account of a new invention for blasting rocks. He writes after an examination of the process :— " The apparatus is the invention of Mr. A. Stickney, of Norwich, Vt. It is a platinum tube about ten inches in length, with holes in its side. Connected with this is an iron tube of any required length. This is the apparatus, and now for the operation. A hole is drilled in the rock to any length ; this tube is filled with charcoal and ignited in the platinum, and inserted in the drill hole. A blacksmith's bellows is applied to the upper end of the tube, and the most intense heat is forced through the small holes upon the sides of the rock, scaling it off in fine powder at a rapid rate. When the heat is sufficient, the tube is withdrawn, and water poured in, which enlarges the hole at the bottom. The effect of powder upon a rock when confined in such a way must be tremendous. The experiment has been tried with the most perfect success." — [Boston Transcript. [To us it appears as if the above invention was both slow and expensive, and not so good for the purpose as the one described by us about two years ago, whereby the bore was enlarged at the bottom by the use of chloric acid. Practice, however, is the proof of the System.