All the preliminaries had been hitherto carried on under the superintendence of Major Douglas, professor of engineering at the Military Academy at West Point; but, owing to some disagreements, Mr.
J.B.Jervis was the engineer eventually selected to carry out the undertaking.

It is but just to mention his name, as the skill exhibited entitles him to lasting fame.

By the construction of a substantial dam, the water was raised 40 feet, and a collecting reservoir formed, of 500,000,000 gallons, above the level that would allow the aqueduct to discharge 35,000,000 gallons a day.

This stupendous work consists of a covered way seven feet broad and eight feet and a half high; in its course it has to pass through sixteen tunnellings, forming an aggregate of nearly 7000 feet; to cross the river Harlem by a bridge 1450 feet long and 114 feet above tide water, and to span various valleys.

The receiving reservoir outside the town gives a water surface of 31 acres, and contains 150,000,000 gallons; it is divided into two separate compartments, so that either may be emptied for cleansing or repair.
From this point the water is carried on, by three 36-inch pipes, to the distributing reservoir, which is 386 feet square and 42 feet deep, but filled generally to the depth of 38 feet, and then holding 21,000,000 gallons.