in America has not yielded to masonry; even in the erection of brick or stone houses, the former has a greater share of work, the latter doing scarcely anything beyond building the outside walls. In American brick or stone houses, about twenty-five times more wood than in European is used. This may have its evils, wood being subject to ignition and not being naturally so endurable as other materials; but it will not take long for Americans to invent some process by means of which wood may be rendered incombustible, and as solid as stone; something in this direction, we believe, has been done already. The bold centering of domes and the slender elevation of steeples on skeletons of wood, as carried in this country, command the attention of foreigners; there are a dash and lightness in those works that bespeak the skill of American carpenters. The mechanical performances of "Sardanapalus" and other plays can not be overlooked in an article referring to carpentry. Nor can we omit to record that American ship-building compares favorably with that of any nation, the English included. Yet all this becomes a trifle if we consider American wood bridges. The Schuylkill bridge, built by Wernwag at the beginning of this century at Philadelphia—a suspension-bridge, 340 feet long—can not but be considered a marvel of art. This bridge would not yield save under a weight of 1,275 pounds per square inch of the lower chord! During the civil war the constructions of the Federal troops astonished the world; to the rapidity with which new bridges were built in a truly artistic and scientific manner, and to the skill of their architects, engineers, and carpenters is due, in great part, the success of the Northern forces.
Carpenters appear to us as the vanguard of progress, the initiators of all movement toward the supply of mankind's first wants. However incomplete, we trust that our sketch will be deemed suggestive enough to show that their history is worthy of being diffused through the medium of a popular publication.
| THE AVAILABILITY OF ENERGY. |
By W. D. MILLER, B.A.
IT follows, as a direct consequence of the most usual definition of matter as "the vehicle of energy," and is also arrived at from experience, that energy never does and never can manifest itself except in connection with matter. And, although we could readily conceive of, and in fact see many instances of, matter without energy, yet no person of sound intelligence, or, as said Newton, "no one with a competent faculty of thinking," could for a moment entertain the idea of energy without matter; and we naturally suspect that anything
