When the building had been lifted to a height of twelve inches, it became necessary to raise the screws. To effect this, two rows of beams (Fig. 7) were added to the timber-work, and each screw was moved in succession, so as to always leave one in position. By these means the building was gradually lifted to the desired height, and it now became necessary to take the requisite measures for moving it back. With this object in view, spruce floor timbers, _e_, very smooth and well lubricated with tallow and soap, were laid upon the timber work and afterward covered with oak planks, _d_, one inch in thickness, and upon these latter were placed joists, _c_, that supported string-pieces, _b_, that were firmly fixed to the joists by means of spruce pins driven in with force. As the floor timbers that were employed had to be as long as possible, they were united end to end by a strong joint and prolonged as far as the new spot upon which the edifice was to rest. Throughout their whole extent they were supported by sleepers that were fixed firmly in the earth. The entire weight of the structure being carried by the pieces, _a_, _b_, _c_, _d_, _e_, and _f_, after the removal of the screws, the jacks, V, were then placed in position, their heads resting against the string-pieces, _b_, at the points marked S, and their other extremities being received by a framework set into the earth. It took but twelve jacks to move the entire mass, and these were maneuvered under the orders of a superintendent, who transmitted his signals with a whistle. It took forty days to perform all these operations, and it required fifty men to lift the structure. After the jacks, V, had been put in place, the building was moved in three days, or at the rate of 11.68 feet per day. This is a medium rate of speed to be adopted in the moving of a structure like this, for, under very favorable conditions, it might be carried to over eighteen feet per day. The timber work which was used in lifting the building was afterward put together again, in the same manner, around prolonged foundations, and the same were put in place a second time after the manner described above. After the floor timbers, e, had been removed by slightly lifting the load, and the structure had been lowered to its proper position, the intervals between the cross-pieces, _a_, and the walls of the new foundations were filled in with masonry; the mass was then allowed to settle gently down into its place and the cross-pieces were removed.