The race is about ninety feet in width, and is furnished with water through the head arches, which allow a passage of water sixty-eight feet in breadth, and six feet in

depth, to which the race is excavated below the overfall of the dam, and of course, room is allowed for a continual passage of four hundred and eighty square feet of water these ;

arches are on the north of the race, and the mill buildings being on the west, the water

passes from the race to the wheels which discharge the water. The mill buildings are of stone, two hundred and thirty-eight feet long and fifty-six feet wide the lower section is ;

divided into twelve apartments, four of which are intended for eight double forcing

pumps the other apartments are for the forebags leading to the water wheels. The ;

pump and forebag chambers are arched with brick, and are perfectly secure from the inclemency of the weather. Those now in use, are kept warm by means of two large iron stoves, heated to great advantage and economy with Schuylkill and Lehigh coal.

It has been from the commencement determined, for the present, to erect only three wheels and pumps, which are now completed, and with them the most important parts of the duty of the committee. The first of the wheels is fifteen feet in diameter and fifteen feet long, working under one foot head and seven feet fall. This was put in

78 PRELIMINARY ESSAY.