REPORT Of the committee of Arts and Sciences of the American Institute, on the model of a wooden bridge, submitted by Lowinan Gay, of Chili, Monroe county, N. Y. The committee, after an examination of the model and an investigation of the principles on which its strength is founded, are of opinion that Mr. Gay has reduced the method of spanning large openings by frames of timber, so combined as to remove all lateral thrust, to the utmost simplicity of which it is capable. In the use of this plan therefore, all costly and heavy abutments are rendered unnecessary, while the combination of pieces in the frame presents fewer parts, and those more skilfully adapted to each other and to the strain to which they are subjected, than in any other plan which has come to their knowledge. The mode of combination of the parts composed of wood, aided by a series of iron rods, appears to render the structure incapable of flexure, until its limit of fracture is approached, while, in consequence of the lightness of the structure, that limit will, in large spans, when the weight of the arch itself is the most important disturbing agent, be removed far beyond that of other analogous plans. They are, in consequence, of opinion, that the frame exhibited by Mr. Gay will be capable of spanning with safety, openings of larger extent than any other with which they are acquainted, and of spanning openings of a given extent, at a less cost of material and workmanship. By order of the committee, JAS. RENWICK, Chairman. American Institute, June 10th, 1816. IMPROVED FAN MILL. Junction, Rensselaer Co., Nov. 23, 1846. MR. T. B. WAKEMAN-Yours of Nov. 1st, informing us that we were awarded the first premium of a silver medal, at the late Fair of the American Institute, for the best fan mill, has been duly received. The required description may be given in a few words. The mill is the ordinary size and construction, as to the exterior; the interior is a new improvement. It is used to clean all sorts of grain and seed raised in this country. Its cost is, for No. 1, with 7 sieves, 16 by 19 inches, $21; up to $27, for size No. 4, with 7 sieves, 19 by 22 inches. They are as durable as cotton machinery, with the same care; easy to be repaired. The amount of labor saved is one-half, as it cleans all kinds of grain and seed clean with one operation. It is the only mill known to the inventor, that will take cockle, chess, and smut from wheat, at the same time it is chaffed. Your ob❜t servants, J. T. GRANT & Co. MANUFACTURE OF UNROTTED HEMP. Louisville, February 23, 1847. DEAR SIR-You made an inquiry of me, some time since, in relation to the process of bleaching flax or hemp; believing now, that the necessity of doing so, in the staple, can be obviated, or is rendered unnecessary, I herewith inclose a sample of unrotted hemp, to establish the fact. I have been engaged with others, for some years, in perfecting machinery that would break and clean unrotted hemp, feeling convinced that if the article could be so obtained, it would prove in cordage, or fabrics, much stronger than that obtained by the uncertain process of either dew or water rotting. You will find, on examination of the sample herewith sent of unrotted hemp, that it has the singular property of being drawn into a very fine sliver, or fibre, this you can prove, by taking hold of the two ends of the sample, and drawing them until the elongation com mences; you can then continue to draw them until the reduction comes down to almost a single fibre. This peculiar property belongs to unrotted hemp alone; and can be accounted for by the starch or gum of the fibre being in a crude or undissolved state. In dew rotted or water rotted hemp, the starch or gum, is dissolved and forms a paste, which, when dry, cements the fibres together, and prevents their free passage in the drawing frame, unless cut down very fine on the hackle. By spinning the unrotted hemp into fine yarns, through the simple. process of boiling them in soap and water, would give them the appearance of half-bleached linen, and they would be found sufficiently white for the best canvass, made or used in this country or Europe. Su:ely, such canvass would be found much stronger than that requiring an acid in the bleaching process, or that made from decayed or decaying heinp. I am convinced that the labor and loss consequent in the preparation by hackling of ordinary h mp, can be entirely avoided by the use of the article we are now preparing; for I believe, that with proper drawing frames, it can be drawn down to a cambric thread, without the intervention of a hackle tooth. I trust the above statement may so far interest the members of the Institute, as to bring their minds to a considerati in of the importance of this staple to our country, for surely, if my views are correct, nothing can arrest the progress of its manufacture, until it displaces, in a great manner, the consumption of cotton in all heavy fabrics at least. It is further interesting to know, that the article can be grown by free labor, and can be produced in every free State in the Union. Yours, respectfully, T. B. WAKEMAN, Esq. JAMES ANDERSON. NEWELL'S PARAUTOPTIC BANK LOCK. The committee of the American Institute, to whom was referred the examination of Newell's parautoptic Lank lock, report: That they have given the subject referred to them a careful and attentive investigation, and have received full and complete explana tions from the inventor. They have remarked in the lock a number of important advantages, and in particular very great improvements upon the permutation lock formerly submitted by him to the American Institute. Thus, while it retains all the advantages of the permutation principle, combined with the property that the act of locking sets the slides to the particular arrangement of the bits in the skeleton key, the parts thus set are completely screened from observation, from being reached by false instruments, or from being injured by any violence not sufficient to break the lock to pieces. Having, in the course of their inquiries, examined the different ex-. isting modes in which locks may be picked, forced, or opened by false keys, the committee have come to the conclusion, that the parautoptic lock cannot be opened by any of the methods now practised, unless by a person in possession of the key by which it was locked, in the exact form of combination in which it was used for the purpose, or in the almost impossible case of the bits being adjusted to the skeleton key by accident in that very form. As the chances of such accidental combination range, according to the number of moveable bits, from several thousands to several millions, to one, the committee do not consider that so small a chance of success would ever lead to an attempt to profit by it. In conclusion, the committee feel warranted in expressing the opinion that, unless methods hitherto unknown or imagined, should be contrived for the specific object, the lock in question may be considered as affording entire and absolute security. American Institute, July 7th, 1816. THOS. W HARVEY, DEPARTMENT OF SCIENCE. REPORT On Browne's Trees of America. The committee to whom this volume was referred, availed itself of the opinions of learned citizens, as well as of its own judgment in deciding to recommend the work, not only to the Institute for a premium, but to the public, and the committee also considered the length of time, the labor and expense, the extensive travel and studious researches of the author. The clear and perspicuous manner in which the subjects are trea!ed, the decided utility of the work, and its mechanical execution, constitute strong recommendations. This book requires also a supplement which the public press has anticipated as requisite to its perfection; that is, a full account of all the remaining trees and shrubs of America, treated in conformity with the plan already adopted in the published work. This book deserves to find a place in all the libraries of the country, including those of all our colleges, academies, and district schools, and for our State and county agricultural societies; and it will constitute a valuable premium to be given to the successful competitors in all our agricultural fairs. H. MEIGS, Chairman. |