This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1883 Excerpt: ...work are now carefully examined, and all inequalities and defects made level with pine wedges. The screws being in position under every part of the structure, and brought up to a firm bearing, the operation of raising is commenced. The workmen are arranged in pairs in such manner as to be opposite each other on both sides of the wall; every mail has from twelve to fourteen screws to operate, and to ensure simultaneous motion, the foreman gives a signal, generally by whistle. Each man thereupon advances the screw under his control one-half revolution, and moves to the next, until all the screws under his charge are advanced an equal distance. This process is repeated, when the signal is given, and the building is gradually raised (Fig. 3) without injurious disturbance to the structure; so smoothly is the work performed, that a stranger would not bo able to detect anything unusual going on. By the first few turns of the screws the intermediate parts of the walls between the needles are torn away from the foundations; but these parts are closely watched, and, if any unusual binding is observed, they are cut out with chisels. After all the screws have been advanced a distance of 12 inches, the work of fleeting (Fig. 6) is commenced, and the necessity of two pairs of screws under each needle is hero apparent. The cribs are built up two courses in height, when one of the two pairs of screws is taken out and placed on top of the cribs as raised, and tightened up to a firm bearing. The remaining pair is then removed, placed on the top and tightened. The operation is repeated until all the screws under the building have been raised, and the structure is lifted to the height desired. Preparations are then made for moving the building. This is effected by placing on t...