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��in 1853, 'There is no perceptible settlement' oftlie base, — a statement which seems hardly accurate, judging from what is usual, and from what appeared later. Here may be mentioned, as of interest later, that the architect, Mr. Milts, in 1848, levelled from the top of the third course or step of the foimdatioD to n point on top of the meridian-stoue monument near tide-waler, planted by President Jefferson, and thus established a refereace by which he might detect any settlement occurring in the progress of the work.
On Feb. 22. 18.)5. congress having been petitioned fur aid, a committee of the house approved of the work done, and recommended an appropriation of 8200,000. But this was the period of the Know-nothing excitement ; and, on the very day that the appropriation was recommended, the books and papers of the monument society were forcibly seized by adherents of the American party, and a new board was illegally formed from their members. This action again delayed progress, and, dur- ing their rule of four years, only four feet were added, bringing the obelisk to the height of 15G feet above the base, at which elevation it long rested. On Feb. 22, 1859, this board was ousted by the incorporation by congress of a new Washington monument society for the purpose of finishing the work. These changes probably account for the more or less complete disappearance of the original plans, measurements, bench-marks, etc., which is afterwards noted. The civil war soon followed, and 00 actual work was done for many years. The society remained as custodian during this time, and made some attempts to rc-awaken public interest. Numerous examinations were made by government olHcials of the condition of the stone work, which in some places was slightly chipped at the edges by fiush jointing, and of the foundation. lu April, 1874, Lieut. Marshall found that the artis of the shaft was inclined 1.4 inches to the north-west. At one time it was hoped that the bare shaft might be finished in some form by July 4, 1876 ; but the unsatisfactory condition of the foundation prevented.
All hope of completing the monument by the centennial anniversary having gone, the matter apparently rested until August, 187G, when an act of congress was approved, pro- viding that tJiere should be appropriated $200,- 000 in four annual instalments, to continue constructioQ ; the officers of the society being required to transfer tlie property to the United States, and the construction of the monument to be under the direction of the president of
��the United States, the supervising architei of the treasury and of the capital, the chief engineers, and the fii'st vice-president of monument society. In the examination cal for in this act, it was very curiously discovered, bj- levels taken to what was then supposed be the meridian-stone previously referred that the moimment had, in twenty-eight years^ settled nearly nine inches into the ground. lively investigation by those most interesl presently developed the fact that Gen. Bi cock, when in charge of buildings and grount in Washington, had, in the course of improvi ments, graded off and carted away the meri< ian-stone monument; so that, added to loss of ail plans and details, we must nowT relinquish all hope of knowing whether the monument had settled or not.
Congress then authorized the re-cn forcing of the foundation; and the work was placed in charge of Lieut. -Col. Thomas Lincoln Casey, U.S. engineers, who had devised, and has suo- cesefully carried' out, the plan shown in the sketch. The cai-th about the base, some 10,- 000 cubic yards, was first removed. Then a trench 4 feet wide, 13.5 fect deep, extending 23 feet outaide of the old foundation, and tua- nelhng 18 feet under it, was excavated. The trench was then filled with concrete of four parts broken stone, three parts pebbles, two parts sand, and one part Portland cement, mixed by machinery iu a cubical box rotating on a diagonal axis, and then thoroughly rammed in place. When the space under the old foun- dation was as nearly filled as convenient, more concrete was put into small gunny-sacks, and rammed home horizontally, while yet sott, with a heavy timber. The order in wbicb these trenches were made and filled is num- bered on the plan. At first it was intended to make and fill two opposite trenches at the same time ; but it was found that removing 144 square feet of the foundation (only 2.5 ^) caused a too rapid motion of the column, and, after the first four trenches, but one tiench was made and filled at a time. This sensi- tiveness of the obelisk to disturbance appears to confirm the opinion that the old foundation was already carrying nearly the maximum allowable load.
The effect of cutting these trenches wa« studied by means of a plumb-line suspended from the top of the shati, and hanging freely through a graduated metal circle near the floor. The greatest movement at the begin- ning of the work was |i of an inch. By careful watching and working, the original delleetiou of 1.75 inches was almost entirely
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