The soil being a loam on a subsoil of gravel, no under-draining was required, except the drains for the water-closets, back-kitchen, and rain-water pipes. For these purposes, each house has a barrel-drain, communicating with the sewer in the road. The general surface, and all the walks in the back garden, incline from one point at a, to another at b, where there is a drain to a small sewer in the back lane. From the point a, to c near the steps up to the front door, the surface of the walk and the adjoining ground is nearly level, but slightly inclining to c; and from c to the street entrance (d) there is a gradual slope of above a foot There is also a very gradual slope of the general surface of the garden1 (say of 3 in.), from the margin of the walk a c d, to the party wall which forms the southern boundary of the garden; and between c and d there is also a gradual slope (say of 6 in.) towards the point e. In consequence of these inclinations of the ground and walks, no rain ever stands on the surface, however abundantly it may have fallen.

The service water-pipes of both houses are laid down along one side of the walks, from d to a, and are thence conducted to main cisterns for the supply of the houses, to others jointly for the houses and the gardens, and to other cisterns for water-closets.