Saliva as Antiseptic. To the Editor of the SCIENTIFIC AMERICAN: I would add a few lines to the observations of Charles A. Nash relative to the sterilizing effect of saliva. Surely one must indeed be blind who has not taken note of the tongue-lapping treatment our dumb animals give their wounds and lacerations, and with no other care such wounds heal in a remarkably short time. I have long since concluded that the best treatment for a wound is a liberal and frequent application of saliva taken from the glands under the tongue. This is a “home remedy” always resorted to with a cut or bruised finger; and while it may not appeal to our refined senses, nevertheless it is Nature's only salve, and may always be applied in the right place at the right time. O. J. REA. Tracy, Minn., November 25, 1907. The Marconi Company's Reply to Prof. Fesseudeu. To the Editor of the SCIENTIFIC AMERICAN: With reference to an article which appeared in your esteemed issue of November 16 last, over the . signature of Prof. R. A. Fessenden, I am directed by Commendatore G. Marconi to inform you, for publication in your journal, that beyond denying generally the statements of Prof. Fessenden and dissenting from assertions made and conclusions arrived at. in said article, he regrets that exigencies of business prevent him from entering into controversy on the subject, but that he simply invites reference to actual statements made by him before British and Italian scientific societies, for which statements he holds himself fully and solely responsible. Com. Marconi desires me further to state that he intends to reserve detailed information respecting transatlantic wireless telegraphy for inclusion in papers which he has promised to read during this coming winter before American and British scientific societies. MARCONI WIRELESS TELEGRAPH COMPANY OF AMERICA. By J. Bottomley, Vice-President. New York, December 3, 1907. An Inventor Who Claims to Have Anticipated Mr, Edison's Concrete House Idea. To the Editor of the SCIENTIFIC AMERICAN: In No. 20, vol. xcvii, November 16, 1907, of SCIENTIFIC AMERICAN, I saw an article bearing the heading "Edison System of Concrete House." After reading over the article I notice that this system consists in the use of concrete pumped into adequate molds, same being spoken of as a new invention. I must state, however, that the said process is not novel, as under date of December 14, 1901, patent No. 2498 was granted to me by the Mexican government covering a new process of manufacturing and building houses or the like in one piece, by means of specially designed molds that let the air escape. The same patent was improved on the 23d of iMarch, 1903, under No. 3503 Us. My system is still simpler than Mr. Edison's, as the mixer is suppressed. I therefore claim as my own the prime idea of manufacturing concrete with a pump into adequate molds, this process being useful for the making of industrial products of every kind and description as well as for building houses, etc. This invention might cause a revolution in the art of building, as construction may be carried out by the use of small pieces of material inwrapped in a semi-fluid mass playing the part of cement, with the object of uniting said material. The addition of iron bars or armature is a factor of security to the rigidity of the products thus obtained. I am still further improving my process so as to make it more practicable. H. J. LECOMTE. Mexico, November 26, 1907. Sustained Flight at High Speed. To the Editor of the SCIENTIFIC AMERICAN: I read with considerable interest Mr. F. E. Stanley's letter concerning recent descriptions and data of flying machines which have appeared in your paper. For the most part I heartily agree with the writer, and it would seem that if the same sort of hard-headed common sense logic had been used by more of the flying machine inventors, less money would have been wasted and the art of flying would be much further advanced. Toward the end of his letter, however, he makes two statements which are substantially as follows: That with equal powers the speed of a flying machine will never be so great as that of a wheeled vehicle. Also that a flying machine can never carry a given weight of pay load as cheaply as a wheeled vehicle for a given distance. His arguments to prove the first statement are based on the comparatively poor efficiency of the air propeller as compared to that of the driving wheels of a wheeled vehicle, and also on the supposition that the air resistance of a flying machine must necessarily be greater than that of a wheeled vehicle. The argument is good and rather hard to refute. The real weakness of Mr. Stanley's argument lies in the fact that he has apparently overlooked the possibilities of soaring, or gliding flight, as practised by most of the larger birds. This phase of aeronautics has from time to time been discussed in your valued paper. Perhaps one of the most exhaustive treatises on this subject is a paper by Octave Chanute which appeared in the Aeronautical Annual of 1896 and 1897. I feel sure that a careful consideration of this subject will convince any thinking person that it is at least possible to fly long distances at high speeds with little or no expenditure of power except that which is external to the machine or bird. I would also cite in support of this assertion the gliding experiments of Lilienthal, Herring, and the Wright brothers. As to the second of Mr. Stanley's assertions, relative to the comparative cost of aerial transportation, I must say that to attempt to refute it at present would be rather a hard task, although if we admit that less power is required to propel a flying machine at a given speed than a wheeled vehicle, we have quite a point in favor of the flying machine. HAROLD H. BROWN. Boston, December 2, 1907.