RErORT OF MR. NELSON L. DERBY.
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longer than the English, ancl the thicknesses fixed are in all cases multiples of the length, breadth and thickness of the bricks. The tendency is, however, in the better buildings, to build walls of still greater strength, and for a variety of reasons. These admit, as before mentioned, of greater projection of cornices; they are good non-conductors of temperature, and remain in good condition even after extensive fires. The large size of rooms in the newer houses, having in general a depth of twenty-four feet, and a height of twelve to eighteen feet, and the great size of the windows, call also for an additional strength of masonry. The latter do not, as with us, slide up and down, hut fold back in two wings on hinges, and generally towards the interior, thus enabling the whole window opeuing to be uncovered, while by our method one-half of it must always remain closed. To prevent the projection of these wings into the interior of the rooms on opening, the walls must be at least three feet thick, of which six inches represent the distance the window is set back from the front, six inches the interval between the exterior and interior windows in case they are double, and two feet the space required for a wing to fold back upon; that is, three feet in all where the window is four feet wide. In one of the new museums building in Vienna, a wall, at the basement twelve feet in thickness and laid in cement, may be seen, and others of five and six feet are by no means uncommon. Numerous accidents have taught the builders care, and where a wall appears of insufficient thickness in the plans, it is customary to lay it in cement and relieve it of the weight of floors as far as possible. In the older buildings, where floors are vaulted from cellar to attic, the amount of masonry in the walls is still greater. The most evident objections to all this are the increased cost of building and the loss of room, which may be met by the fact that in Vienna, and the Italian cities where similar laws are in force, fires are infrequent, and if occurring, are productive of little damage ;—the additional cost may thus be looked upon as a good investment of capital. If such regulations cannot he introduced in general in America, something might be done to insure the safety of human life, in theatres and hotels especially, by requiring the construction of substantial and fire-proof stairways and passages.