gitudinal compression appears to be diminished 18 times.—(Leslie's Elements, and Duhamel in Mem. Paris. Acad.) 37. Mr. B. Bevan has favoured the author with a tabular view of his results with regard to the modulus of cohesion, or the length in feet of any prismatic substance required to break its cohesion, or tear it asunder. The following, also, exhibits Mr. Bevan's results as to the modulus of elasticity. feet. Many other results are collected in Mr. Tredgold's Essay on the Strength of Cast Iron, a work which may be consulted with advantage on this and kindred topics. Indeed, we have not aimed at more in this section than a brief summary of the leading principles involved in the consideration of passive strength, and a corresponding exhibition of the best ascertained facts. The subject is one of great and growing interest to all concerned in the erection of extensive structures. Such may consult, in addition to the volume just mentioned, Tredgold's Carpentry, Barlow on the Strength of Timber, Gregory's Mechanics, Vol. I., the Lectures of Dr. T. Young and Professor Leslie, already quoted, and Girard, Traité Analytique de la Résistance des Solids. |