W. B., of Pa.—You express yourself somewhat surprised to see Mr. Mills scheme published in the Scientific American. It may or may not be practicable—we did not decide upon this point—we presented the subject as one of novelty and interest, our readers are not obliged to believe in it, and there is no reason why we should not publish it as we do many other new and untried schemes. Let us have all sides fairly presented. We will decide upon what shall or shall not appear in this paper, and employ our own terms in dealing with all subjects. V. L. M., of Pa.—On the New York and Philadelphia Railroad, the curtain which you describe is employed on the cars to prevent the rising of the dust from the track. It was suggested by an eminent mefhanic living in this city—it works admirably, and we hope to see other roads adopting it H. J,, of Ind,—We expect soon to publish engravings of Irving's Boiler, then you can readilyunder-stand the principal upon which it operates, H, T. R, ofN. H.—Explain what you mean by anchors for stopping railroad trains. The mere idea is not patentable. You must fix your ideas into a tangible contrivance. A. C. C, of Tenn.—It is impossible for you to make the rails answer the purpose of a covered wire. You cannot properly isolate them. You may be sure of this. W. T., of Me.—We see nothing new or patentable in the plough, but the fence appears to possess novel features. R, of Nova Scotia.—Richard Kitson, sf Lowell, Mass , can give such information as you desire in regard to oakum. W. J. T., of N. Y.—We received your letter of June 6th, and replied to it very promptly, the reply missed you it appears. We advise you to send us a model of your measurer T. B.j of Ind.—There isnothingpatentable in your method of coupling, we have seen the same thing before used in carriages. J. A. T., of Miss.—G. Page, of Baltimore, Md., or Geo. Vail, & Co., Morristown, N, J., canfurnish you with portable saw mills. The clock work, for fanin rooms was invented and patentee by Com. Barron, 1830. A. G., of 111.—Yours came too late f cr this num- ] ber. It was a most unjust act in your case. E. J. H, of Pa—Mr. R. is now at Niagara Palls, j superintending the erection of a new suspension i bridge; we have not seen his article but will look ? for it ; M. B., ofN. H.—You have never read the history . of the steam engine; read it. L L , of Ohio.—The papers of the scientific association will be published by the city authorities of Cleveland. * H. McN., of Conn.—There is no difference between i your principle for heating apartments and heating > ihfftaiiy steam Ipes connected with a boiler. ' J. R.M., of Pa.—We have no faith in the value since for essentially the same thing. T 1 W of England—We do not know of " self-acting gates at railroad crossings," like the ono de-cribed in your letter ; there are, however, good gates here for the same purpose, but railway companies do not feel willing to trust them. Money received on aeemt of Patent Office business for the week ending Saturday, Aug. 13 :-H. L. E., of Mich., $60 ; J. L. L. M, of Pa , $30 i W. MoB.,of Ohio, $30 ; J. P. H., of Ohio, $30. Specifications and drawings belonging to parties with the following initials have been forwarded to the Patent Office during the week ending Saturday I ASgp., of N. Y (2 cases) ; H. A. C, of Mans. ; W-M. &K, of 111 i W. F. M., of N. Y. ; A. E. B., of N. Y.