The service-pipes to each house are more perfect mechanical contrivances; but they could not have been rendered so perfect without engines, which force the water above the level of the source from which it is taken. When the inhabitants fetched their water from the springs and conduits there was a great deal of human labour employed; and as in every large community there are always people ready to perform labour for money, many persons obtained a living by carrying water. When the New River had been dug, and the pipes had been laid down, and the engines had been set up, it is perfectly clear that there would have been no further need for these water-carriers. When the people of London could obtain two hundred gallons of water for twopence, they would not employ a man to fetch a single bucket from the river or fountain at the same price. They would not, for the mere love of employing human labour directly, continue to buy an article very dear, which, by mechanical aid, they could buy very cheap. If they had resolved, from any mistaken notions about machinery, to continue to employ the water-carriers, they must have been contented with one gallon of water a day instead of two hundred gallons. Or if they had consumed a larger quantity, and continued to pay the price of bringing it to them by hand, they must have denied themselves other necessaries and comforts. They must have gone without a certain portion of food, or clothing, or fuel, which they are now enabled to obtain by the saving in the article of water. To have had for each house two hundred gallons of water, and, in having this two hundred gallons of water, to have had the cleanliness and health which result from its use, would have been utterly impossible. The supply of one gallon, instead of two hundred gallons to each house, would at present amount to 310,000 gallons daily; which at a penny a gallon would cost 1291_l._ per day; or 9037_l._ per week; or 469,724_l._, or very nearly half a million, per year. Upon the assumption that one man, without any mechanical arrangement besides his can, could carry twenty gallons a day, thus earning ten shillings a week, this would employ no fewer than 18,074 persons--a very army of water-carriers. To supply ten gallons a day to each house would cost nearly five millions a year, and would employ 180,740 persons. To supply two hundred gallons a day would require 3,614,800 persons--a number exceeding the total population of London. The whole number of persons engaged in the waterworks' service of all Great Britain is under 1000. [Illustration: Old water-carrier of London.]