Two-thirds of the usual expense of street cleansing is the expense of cartage, which, with a proper adaptation of the sewers, is wholly unnecessary. The exclusive use of hand-labour in street-sweeping is pronounced by competent judges to be a mere barbarism, and several machines have been invented which demonstrate that by mechanical power, moved by horses, the cleansing may be effected in a far shorter time. Some of these scrape the mud in ridges to the sides, where it remains until it can be lifted and carted away. But this is objected to as inconvenient by the shopkeepers, and the scavengers object that it is no convenience to them, inasmuch as raking it in heaps prevents the evaporation of the liquid, and increases the cartage; and, moreover, that the process of sweeping by hand is as quick as the carts can return for its removal. A machine has been used at Manchester which rapidly and cleanly sweeps the level surfaces of the streets into a cart; but there is still the encumberance of the labour, and cost and delay of carting the refuse to a place of deposit, which may be several miles distant, and returning to reload. The value of a process of street-cleansing is proportioned to the rapidity with which it is performed, but at present it is usually delayed until the sun or the air has done a large portion of the work by the evaporation of the moisture, commonly however to the deterioration of the air of the town and the health, and also to the deterioration of the value of the refuse. On examining these obstructions to the cleanliness and salubrity of our towns, it became apparent that the expensive and slow process of the removal of the surface refuse of the streets by cartage might be dispensed with, and the whole at once carried away by the mode which is proved, in the case of the refuse of houses, to be the most rapid, cheap, and convenient, namely, by sweeping it at once into the sewers, and discharging it by water.