Appleton's cyclopædia of drawing, designed as a textbook for the mechanic, architect, engineer, and surveyor (1866)
Worthen, William Ezra, 1819-1897, [from old catalog] ed, Appleton, firm, publishers, New York. (1866. D. Appleton & co.) [from old catalog] · New York, D. Appleton and company · leaf 348
tructure should always be in onedirection. It follows, from what has been shown of the effect of a variable load,that no bridge, either straight or arched, intended for the passage of heavyvehicles or trains, should ever be without counter braces or diagonal ties,and that only in the case of roofs… … Fig. 4T. ticity of iron is very small in comparison with wood, w^hen iron is thusused to truss timber, the rods must break before the beam reaches the de-flection that the weight should produce. It is evident, therefore, that inconstruction the beam should not be cambered by the tension of therod,…
