W. B. B., of Pa.—Minnifie's Drawing Book, coes $3 bound, or 25 centa a number in sheets, published monthly. J. E, T., of N. Y.—We cannot act as the medium for advertisers and applicants to correspond through —therefore we do not admit advertisements which refer to us for further information. Your advertise ment we have inserted over your own name and place. F. B. W., of England—Your subscription will ex pire at No. 30, present volume; you had better en close to us a sovereign and send by mail for continu ation of the paper, or you may pay our agents in London, Messrs. Avery, Bellford & Co , 16 Castlest, Holbprn. We iiave not a copy of No. 19 left. S. H, A.j of N. Y.—You have made a complicated engine to obtain what is obtained by a steam jack et, as employed in the Cornish engines ; do not trouble yourself any more with it. P. B., of Masa.—If we understand you properly we should think your alleged improvement in wagon wheels not new. We think we have seen the same thing before, but could not tell without having a chance to examine a sketch. $4 received. T.Q-. N.. of N. Y.—There is no work upon boiler making of any practical value : Tredgold's work on the Steam Engine is the best, when done it will cost $50 or $75 ; Griffith's Naval Architect is a work of much value, price, bound $12. W. T- S , of Boston—Nasmyth's steam hammer is the one which we suppose is most suitable for you. Merrick & San, Philadelphia, are proprietors of the patent. S S, of C. W.—If you put a quantity of sweet oil in jour made soap ; it will keep soft and cream like j the substance, which makes soap wash in hard water, is an alkali—an abundance of soda or pearl-ash ; borax dissolved in water and used in soap lath er makes it agreeable for shaving ; it can be used in the soap in place of pearl ash The small "Erics sons" you will never see. We will comply with your request about the subscribers. J. C. H., of N. Y.—You must give the finishing touch with fine Tripoli. J. N. P., of Mass.—The arrangement of your en gine appears to be new, but we cau see no advantage in it not already gained by engines in common use-We think your views predicated upon a false basis. Experiment will determine this point more satisfac torily than opinion; the apparatus is too compli cated, J. S , of Pa,—We can see no patentable feature in your friend's method of operating the rudder of steamboats ; substantially the same plan has been employed, but with what success we are unable to say. R. E,, of 111.—We do not see how it is possible te arrange circular saws on a new mandril for sawing out wagon felloes and curvUinear work, we do not know of any thing of the died. T. S. J., of Ohio—About the time the California excitement broke out, we were shown a device for guiding a balloon similar to yours. We cannot say what it would do, as no trial was made with it. C. C, of Mass.—Your device for breaking up rail-load trains appears to be novel. Its advantages must be made the subject of a test, we cannot de cide this question without, as the idea is crude. W. B. D., of Mo.—The business at the Patent Of fice is very much behind, and is growing more so every week. We file from our office nearly as many applications every week as the Department grant Letters Patent, exclusive of the applications made from other sources. Yes, it is too bad: more Ex aminers should be appointed. We have had some oases before the Oflice four and five months. B. B., of N. Y —Your device for cutting dovetails is not patentable: essentially the same thinj? has been used for the same purpose. G. J., of Ohio—There is nothing new, useful, or patentable in your device to be used as a substitute for the crank ; it is preposterous and unworthy of your attention. J. S.. of Ky.—You have lost your right to the pa tent, having virtually abandoned it to the public. You could contest it with Mr. M, but without hope of reward, even if (successful in gaining the point of priority. 0. P, B., of Tenn —We placed $1 to your credit for advance subscription. If you have any business to transact with us please send a model. W. R, G-., of Ky.—Your method of ventilating cars is not new, the same device was shown in seve ral models exhibited at the last Fair of the American Institute. A, H., of III.—In the year 1840 a model was ex hibited before the members of the New York Legis lature, which embraced tha same ideas as are found in Mr. C 's engraving; this fact we have lately learned from an eye-witness. He has no patent and we believe cannot obtain one. Money received on account of Patent Oflice busi ness for the week ending Saturday, March 19 :— E. F., ofCt , $50 ; R. M P., of N. Y., $35 ; W.W-of Conn , $30 ; J, B. T., of N. Y.s $25 : 0. S. T, of Ct. $30 ; J, A. B., of N- Y., $25 ; A. S- N,, of Pa., $55 ; J. P. A., of Ct., $25 ; T. H. T., of N. Y., $30; 0. D. D.. of N. Y,, $300; P. W., of Me., $55 ; D. A. M , of Pa., $55 ; G. W. F., of Ohio, $55 ; P. K., of Ct , $20. Specifications and drawings belonging to parties with the following initials have been forwarded to the Patent Office during the week ending Saturday March 19 :— J. S., of N. Y. ; J. B. T., of N. Y. ; J. A. B., of N. Y.; C. D. C, of Mass.; J. C, of Ga.; N. C, of N. ; Y.; T. F., W-, of N. Y.; T. H. T., of N. Y. ; J P. A.,ofCt.