enjoy of a domestic supply delivered under pressure into each of their houses.

Coming to modern times, the distribution of a domestic supply dates back from the time of Peter Morice, who, in 1582, erected waterworks for the supply of the City of London by means of pumps actuated by water-wheels placed in the first two arches of old London Bridge. He appears to have distributed the water under pressure through leaden pipes, but it is probable that a few years later these were replaced by wooden pipes, which, as early as the year 1628, were being laid down by the New River Water Company. These wooden pipes consisted of the trunks of elm trees, cut into lengths and bored longitudinally to an internal diameter of from 6 to 12 inches, in accordance with the internal pressure they were required to withstand. In the parts of the town lying at the lower level (where the pressure would be greatest), the diameter of the bore would be 6 inches, so as to leave a considerable thickness of wood between the inside of the bore and the outside of the tree. In the higher parts of the town, and near the reservoirs, where the pressure would be less, the bore would be gradually increased to 12 inches in diameter, a less thickness of timber being required in those parts. The joints of these wooden pipes were made by forming one end of the tree into a conical shape, and hollowing out the other to correspond; the several lengths, when laid, being then driven one into the other.

These wooden pipes, however, proved very defective, as the loss by leakage was estimated at not less than onefourth of the whole quantity flowing through them. From decay and other causes they required also to be renewed on the average about once in every twenty years; and consequently, as at one time the New River Company had 400 miles of these pipes laid down, they had to take up and renew upwards of 20 miles in length each year.

Owing also to the small diameter of these wooden pipes, where they had to bear any amount of pressure, more than one line-and in one case no less than nine lines—of pipes

had to be laid side by side in the same street, in order to furnish the requisite supply.

When we reflect on the fact that at this period London was almost entirely without under drains, we may be able to form some slight idea of the terrible amount of moisture with which the foundations and basements of the houses adjoining these lines of leaky pipes must at all times have been saturated, and the disturbance which the constant repair and renewal of these pipes must have occasioned to the roads.

Bad, therefore, as matters are at the present time in London and other large towns, from the disturbance of the streets for such repairs, we of the present generation may congratulate ourselves upon the fact that, notwithstanding we now have gas-pipes, sewers, and under-ground electric wires in addition to water-pipes laid under the streets, the annoyance which we suffer from street disturbance is as nothing compared with that which our ancestors must have had to put up with in this respect.

There are no records to which the writer has access showing whether, in these early times, the supply for domestic purposes was on the constant or the intermittent system, nor whether the water was delivered at the ground floor of each house only or at a higher elevation. With wooden distribution pipes, such as these described, it would be very difficult to have a proper service of stop or shut-off valves, even if an efficient stop-valve for working under pressure were then invented. The frequent stoppages for repairs would necessarily assimilate the arrangements for supply to those of the intermittent system, which involves the necessity of having tanks, butts, or other capacious receptacles for the storage of water in each house.

In the early part of the present century, cast-iron mains began to be substituted for wooden water-pipes, and by the year 1820 the whole of the wooden pipes belonging to the New River Company had been removed and replaced by cast-iron ones. The substitution of cast-iron for wood introduced a new era into the art of water distribution, as

much higher pressures were rendered available, and leakage was materially reduced. The early cast-iron pipes, although made of the finest cold blast metal, were very rough productions. They were all cast horizontally, and in numerous cases, owing to the imperfection of the machinery, they were far from being either cylindrical or concentric, and thus were frequently thicker on one side than the other. They often, therefore, gave way when exposed to the working pressures they were called upon to sustain, the methods of testing them previous to their being laid being primitive and inefficient.

The first cast-iron distribution pipes were made with flanges on the same principle as the ordinary cast-iron pump-trees. These flanges were fastened together with bolts and nuts, the joint being made between the flanges, with an iron ring covered with tarred yarn or flannel. This method, however, soon had to be abandoned, as owing to the expansion and contraction of the pipes consequent on the changes of temperature in the water passing through them, the flanges were frequently torn off, and hence stoppages for repairs were numerous.

This defect was overcome by the introduction of the spigot and socket-pipe. The early joints of these pipes were made by driving soft wood wedges into the sockets, which were made wide for the purpose. When the wedges had been driven into the sockets as far as was considered prudent, the ends projecting beyond the sockets were cut off, and a few small iron wedges were then driven into the wood for the purpose of giving a final tightening. These joints were found to be a great improvement on the previous system of flanges; but as the wooden wedges became saturated with water, they expanded, and frequently burst their sockets. This led to the abandonment of the system of jointing pipes with wooden wedges, and to the adoption of the plan of filling the back part of the socket with yarn tightly rammed in, and then running the remainder of the socket full of molten lead, which on cooling was caulked up, and so made a tight and permanent

joint capable of withstanding the full pressure to which the pipe might be subject, and, at the same time, of allowing for expansion and contraction without leakage.

This method, for the first time, gave those responsible for the distribution of water under pressure the advantage of having at command continuous distributing tubes of any length, and practically water-tight under any ordinary pressures.

The lead joint, as above described, with variations only for reducing the weight of lead used, or for adding to its security against being blown out by back pressure, has remained a permanent institution, a bar of lead being occasionally substituted for the molten metal.

In some cases, the old-fashioned method of jointing the wooden pipes has been imitated in their cast-iron successors by turning a conical end to the spigot, and boring the socket, so that, when fitted together, the pipes practically joint themselves without any other stopping.

With the introduction of cast-iron pipes, and greater pressure, the system of intermittent supply became more completely developed and established.

Under the intermittent system, the supply of water was not constantly laid on, as is now almost universally the case. The arrangement was to turn on the water from the principal main into the subsidiary distribution pipe, in any particular street, for an hour or an hour and a half a day; during which time all the people in that street had to draw and store a sufficient supply for the remainder of the twenty-four hours.

This system, with which the public were long content, ultimately fell into disfavour. Its inconveniences were great; the water was, as stated, only turned on for a very short time; the system necessitated the employment of a large number of turncocks, whose sole business it was to go round the districts to turn the water on and off. The intermittent system was also injurious on sanitary grounds, as it frequently happened that the vessels in which the water was stored were exceedingly foul, in consequence of

putrefying sediment left in them from previous supplies, and the stored water itself was apt to become impregnated with poisonous gases rising through the waste or overflow pipes of the cisterns which were connected with the sewers. The sanitary defects thus inherent in the intermittent system were the fruitful source of disease and death, and early engaged the attention of the Board of Health presided over by the late Earl of Carlisle, and of which Mr. Edwin Chadwick, C.B., was the earnest and indefatigable secretary. After much inquiry the Board came to the conclusion that these evils could be remedied by the adoption of the constant supply system, which had been introduced at Nottingham by Mr. Thomas Hawksley, past president of the Institution of Civil Engineers, and was in successful operation there on a large scale.

Under the "constant" system, the supply is kept on the whole twenty-four hours, so that anyone, at any time of the day or night, by simply turning a tap in the house, can obtain a supply direct from the main without the intervention of any intermediate storage vessel.

When the proposition for affording a supply on the constant system was first broached by the Board of Health, it was met by a storm of opposition, some engineering advocates of the old system going so far as to allege that it would be a sheer impossibility to carry out the constant system, on account of the uncontrollable waste that would result from having the water always "on," and because, as there was no guarantee that everybody would not be drawing water at the same time, the main pipes would in consequence have to be of enormous magnitude compared with those necessary under the intermittent system, under which system it was alleged the supply could be more. judiciously and economically manipulated.

The controversy on this question raged with great vigour from 1845 to 1850. About that time Sir Robert Rawlinson, C.B., having occasion to visit Wolverhampton in connection with a local inquiry under the Board of Health, asked the writer, who had then recently converted the