377. There occurs another kind of combination against the public, with which it is difficult to deal. It usually ends in a monopoly, and the public are then left to the discretion of the monopolists not to charge them above the growling point--that is, not to make them pay so much as to induce them actually to combine against the imposition. This occurs when two companies supply water or gas to consumers by means of pipes laid down under the pavement in the street of cities: it may possibly occur also in docks, canals, railroads, etc., and in other cases where the capital required is very large, and the competition very limited. If water or gas companies combine, the public immediately loses all the advantage of competition, and it has generally happened, that at the end of a period during which they have undersold each other, the several companies have agreed to divide the whole district supplied, into two or more parts, each company then removing its pipes from all the streets except those in its own portion. This removal causes great injury to the pavement, and when the pressure of increased rates induces a new company to start, the same inconvenience is again produced. Perhaps one remedy against evils of this kind might be, when a charter is granted to such companies, to restrict, to a certain amount, the rate of profit on the shares, and to direct that any profits beyond, shall accumulate for the repayment of the original capital. This has been done in several late Acts of Parliament establishing companies. The maximum rate of profit allowed ought to be liberal, to compensate for the risk; the public ought to have auditors on their part, and the accounts should be annually published, for the purpose of preventing the limitations from being exceeded. It must however be admitted, that this would be an interference with capital, which, if allowed, should, in the present state of our knowledge, be. examined with great circumspection in each individual case, until some general principle is established on well-admitted grounds. 378. An instrument called a gas-meter, which ascertains the quantity of gas used by each consumer, has been introduced, and furnishes a satisfactory mode of determining the payments to be made by individuals to the gas companies. A contrivance somewhat similar in its nature, might be used for the sale of water; but in that case some public inconvenience might be apprehended, from the diminished quantity which would then run to waste: the streams of water running through the sewers in London, are largely supplied from this source; and if this supply were diminished, the drainage of the metropolis might be injuriously affected.