whom he served ; and he was engaged in a series of notable fog-signal experiments, on the transmission of sound through the air along the sea coast.
In 1877 he came to Washington, and as assistant engineer to General (then Colonel) T. L. Casey, U. S. A., took charge of the construction of the building for the State, War and Navy departments. In place of administration ill-defined and expensive, through lack of plans and systematic management, the efficient oversight of Mr. Green resulted in the construction of the north wdng of that building for one and one-half million dollars less than its counterpart, the south wing, had cost; and the cost of the entire building was reduced by some two and a quarter millions below the total which it would have cost if continued under the earlier plan and management.
As assistant to Colonel Casey, Mr. Green was engaged on the Washington aqueduct, especially in extending it as to subsurface conduit. Mr. Green devised the main scheme for strengthening the old foundation of the Washington monument by under-pinning it with concrete; he solved the peculiar problem of the marble pyramidion, the pointed crown on the thin (18 inch) edge of the marble shaft, inventing a special scheme of construction, and himself working up the detail drawings; he also devised and installed the plummet apparatus by which the slightest movement of the center of gravity of the structure may be observed to the one-thousandth of an inch.
He supervised the erection of the Army Medical Museum and Library, and the remodeling and construction of several of the large buildings of the United States Soldiers' Home. In the spring of 1888 he took charge of the construction of the building for the Congressional Library, laying the first half of the foundation in the summer of 1888. When the direction of this work was, by the Act of October 2, 1888, transferred to General Casey, chief of engineers of the army, Mr. Green was made superintendent and engineer in local charge of the entire work, including the architectural designing and construction throughout. This business he conducted at the office on the site of the building. On the death of General Casey, March 25, 1896, Mr. Green was given full charge, as director, manager and disbursing officer. He completed the building on time, and materially within the estimated cost, March 1, 1897. He was by law retained in charge until July 1st of that year, when he was appointed by the President
