The first important application of the method of lifting massive
structures and moving them to another spot was made two years ago at
Boston, Mass., in the moving back of a hotel that stood about fourteen
feet on the line of a proposed widening of Tremont Street. Since that
time several analogous cases have occurred in several cities of the
United States, so that, for this sort of work, a general method of
operating has been devised, notwithstanding the special difficulties
that present themselves according to the different methods of
construction and the surroundings.
All structures, before being moved, must first be separated from their
foundations and then raised. These operations are certainly the most
costly and those that take the longest time. It is necessary to take
minute precautions and to exercise great watchfulness in order to
succeed in planting solidly on the ground the timber work that has
to support the pressure of the screws by means of which the entire
building is to be afterward raised. The success of the operation
depends absolutely upon the care and attention that are bestowed upon
these preliminary operations, since the least negligence may lead to a
disaster.
[Illustration: FIG. 9.--MOVING A HOUSE BETWEEN TWO FIXED WALLS.