212 MEMOIR OF THE tra thickness) has been constructed, and covered with earth to protect the sides and top from frost ; the earth covering being secured by turfing carried over from parapet to parapet. The work presents a very substantial and finished appearance. RECEIVING RESERVOIR. This reservoir is 1826 feet long and 836 feet wide, and including its embankments contains 35.05 acres, and its area at top water line, 31 acres, divided into two divisions the northern division is designed to contain 20 feet depth of ;

water, and the southern 30 feet depth. But they are not fully excavated in some parts, where rock occurs, it not being deemed sufficiently important to incur the expense of excavation in rock for the increased capacity that would be obtained. The reservoir has a of 150,000,000 as it now stands. The reservoir is formed with capacity imperial gallons, earth banks, the interior having regular puddled walls to render them impervious to water ;

the outside protected by a stone wall, laid up on a slope of one horizontal to three vertical, the face laid in cement mortar, and the inside dry the inside is protected by a dry slope ;

wall, laid on the face of the embankment, which slopes 1| horizontal to one vertical. The embankments are raised four feet above the top of water line, and are 18 feet wide on the top, excepting the high banks on the sourthern division and the western bank on the northern division, which are 21 feet wide. The greater part of the embankments for the northern division are of moderate height but a portion of the eastern and western banks ;