H. G., of 111.—Tour letter covering $21 for subscribers was duly received. We have entered all the names for 1 year each, and sent as many oack numbers to the first six on your list as we have got, and regret very much that we cannot furnish them complete. W. Co., of Ohio.—We have no one cent stamps to send, and have applied th dollar received from you towards the continuation of your paper. J. T., of Md.—Your advice is not appreciated, and we very much question the motive that induced your remarks. W. H. M., of lad.—The engravings of your invention will appear in the next number. R.McK.,ofInd.—A pamphlet will be issued in a short time containing useful receipts at a low price. The majority of receipts published in books are not correct. T. T. GM of Pa—You should write to the Patent Office for such information as you solicit of us. If you have been swindled by your agent we regret y your misfortune, but cannot intercede in your behalf until you have first withdrawn your business from his hands. H. L. A., of Wis.—You are correct about the cooling of the cylinders with the cold water. You can avoid this by using a steam engine of the usual form, one double-acting cylinder, and a double act ? ing pump. You will thereby have just the same parts in your engine. J. J., of Miss.—Your engine at that pressure will be about 4 horse power. The power will be found out by multiplying the pressure in pounds on every square inch of piston into its velocity in feet per minute, and dividing by 33,000. A. G. C, of Mass—Yours is such a case that we could not say much about it. There are persons in Boston who are very enterprizing about such matters We have seen a machine professing to accomplish the same thing. J. S. S , of Phila.—Air cannot be employed in any manner to successfully compete with steam, it is too bulky, its nature is not the thing. J. M. S., of Mich.—We cannot judge of your brake without the opportunity of examining a sketch. So many modifications having been made in brakes and the means of operating them that it is almost impossible for us to give a satisfactory opinion without. J. de B.j of Ohio.—J. B. Creighton, of Tiffin, Ohio, is the inventor of a machine for pulling stumps, which is capable, we should think, of performing satisfactorily. You might ascertain by writing to him. T. So H., of N. 0—Messrs Sarony So Major, of this city, could get you up a lithograph of carriages suitable for a show bill. You had better write to them about the matter. J. H. C, of Pa.—There is nothing especially im-portanfcia ywg -wmj."- We may, nPwWf, pW lkh it at some future time, for the benefit of all whom it may concern. C. A., of Va,—The use of caloric as a substitute for steam, would undoubtedly prove a boon to mankind if made successful. We would gladly chronicle its triumphant success, but we are convinced that it is based upon a mechanical fallacy, which time is rapidly developing. We could not withhold our opinion and do justice to those who expect us to speak out. Among the most painful duties we are called upon to perform, is to oppose the claims of inventors, we must do it, however, when such claims are contrary, to established facts, let the consequences be what they may. 0. D , of Ga,—There is such a contrivance ax alluded to in the article in question, which may be1 thus briefly explained : a light bar is placed horizontally near the paper, and on it are secured two or more curved strips of steel, by slightly turning the bar these strips of steel serve as a species of rake to pull forward the paper and present it to the fingers. This motion is given at the proper time by a cam, and the operation is further assisted by a slight tilting motion which is given to the feeding board. It is not, however, to be inferred that this apparatus dispenses with a person for feeding, its object being merely to ensure correctness. H. C, of Me.—It is possible that your " close analysis " of the Caloric Engine may turn out the same as in the case of the "Static Pressure." By reference to a letter you wrote us August 2nd, 1851, you make use of the same terms in approbating the claims of Sawyer So Co. We are probably more particular and less enthusiastic in our examination of scientific matter. Your advice might be useful if properly applied, but not needing it ourselves we must beg of you to withhold it for self-instruction. C. A., of N. Y.—We are disposed to give you all proper credit for your exertions ; the result of your labors are'certainly commendable, and we are sorry that you have been anticipated by others. Money received on account of Patent Office business for the week ending Saturday, April 9 :— H. S. W., of O,, $20 J S. McK.,of N, Y., $30; C. V. D. H., of N. Y., $45 ; J. G-" Jr., of Mass , $60 ; J. O., of N. Y., $25 ; P. K., of Ct., $8 ; C. Co., of N Y., $40 ; H. C. H., of N. Y., $60 j F. D., of Va., $55; H B., of Ct, $25 ; Dm E. McD,, of N. Y., $50 , G, B. Jr., N Y., $30; E. A.S., of N. Y., $45; L. S , of N X, $20 ; W. W , of N. Y., $30 ; B. D, G.. of Miss., $20. Specifications and drawings belonging to partiel with the following initials have been forwarded tc the Patent Office during the week ending Saturdaj April 9 :— P. R., of 111. ; H. H., of N. Y.; J. T. D., of N l Y. ; W.W., of N. Y. ; R. M. F" of N. Y. ; P K., o LCt.; C. S.,of N. Y. ; E. A S., of N.T.; H. B.,o Conn..