T. W., of Ky —Several attempts have been made to use steam carriages on common roads j in point of economy they will not answer. S. W., of Pa.—The method of treating journals is verygood.it is similar to Babbitt's. The difference between the liquid and the gas of carbonic acid is 2000, that is, 1 cubic inch of the liquid will expand to 2000 cubic inches; it ia however, very difficult to tell the exact expansion of this acid, for it is exceedingly sensitive to heat and cold. H. W. H , of Va,.—We Will wait until you arrive with your model, Bo as to obtain more pointed information respecting its merits. W. F , of Mass.—We understand you now ; you may rest assured that you could obtain no " power " equal to that expended in revolving or vibrating your machine. C. S.,of Mass.—We believe that the faculty of judging of colors is as strong and universal in men as women. We do not see a reason for placing the evidence of this faculty in the eye-brow ; we do not know a single person afflicted with this disease. S., of E.—We cannot see how your funnel boiler feeder can operate at all. Z. E. C , of Ct.—There is a mode of reducing hard steel so as to make it forgible ; the mode you can find in any good work on metallurgy ; it would occupy too much room to give you the information through our columns. B., of Mo.—We are not aware of an apparatus in existence for making ice, without an air-pump and freezing mixtures, that is, in warm and in temperate weather. J. K. E, of Ohio—The "relay magnet" is'for the purpose of closing the circuit to make the local bat; tery operate the receiving magnet; this was a great imprcvement when invented. Tour plan cannot meet the case, as the size and multiplicity of magnets are not the tilings required. W. T. C , of Ohio—There is no patenton thechain pump ; we do not know the price of the article in this market; your subscription expires with No. 26, Vol. 9. A. H. Co., of Mass.—We will endeavor to procure and publish the specification of Mr. E.'s patent. J. S., of N. Y.—The extra weight will be an objeo. tion to the car; so much so as to preclude the possibility of its introduction j one ton and a, half is too much of an increase in the weight of a single passenger car. E. D., of Pa.—As we understand your letter (your pencil sketch is too obscure), your steam pump is operated upon the same plan as that of Worthington Baker's j as described by you, it appears to be the same, only you take your steam at thn middle of the slide, which is not new. J. P., of N. 0.—There are no infallible rules for detecting counterfeit money; it requires practice and eonstautknowjedge of money to do it.___ ~- ~~3Tk , oTl?a.—We have never seen the same plan of bandins and pullets in use as that which you propose, and consider it patentable if useful j but we cannot see any advantage to be derived from it; experience, however, and fair trials have perhaps proved ita advantages to yon, and you can therefore prove its utility. O. L. B, Jr, of Ct.—Gut wynne' pump; for more information see the advertisement in ome of your recent back numbers of the Sci. Am. Money received on aocount of Patent Office business for the week ending Saturday, Aug. 27 :— Q. W. B., of N. Y., $372,50 ; W. C , of 111.. $30 : G. J. P, of Mass., $30 I L. P., of Vt., $50 : F. B, ofVt., $25; H.L., of Mass., $25; E. K.,of Mass $40; W. C, of Va., $30; B. D., S., of Va, $105; T. Sons, of N. Y., $200 ; J. J., of N. Y , $55 E J M , of Conn., $30; G. G., of Me., $35. Speciacations and drawings belonging to parties with the following initials have been forwarded to the Patent Office during the week ending Saturday Aug. 27:- L. P., of Vt, (2cases); D. E. McD., of Mass.; G. H., of N. Y.; J. W. M., of Ala.; J. B. M., of Ohio; H. S. B., of Mich.; J. 6 , of N. Y.
This article was originally published with the title "To Correspondents"