544

HISTORY OF ENGINEERING.

Book I.

There is also a great want of uniformity in the practice of the several commissionsand their officers, which requires immediate improvement ; among other points noneis more important than the form given to the sewer, which differs in all the variousdistricts. That used in Westminster has a curved bottom, perpendicular sides, and a semicir-cular top; that in Finsbury is the section of an egg, with the small end dowmwards. Forevery foot of the Westminster of the first class, 261 bricks would be required, and for theegg-shaped only 175, besides which for the latter there would be less digging. Othersare built nearly cylindrical.

Recently, however, the egg-shaped sewer has been introduced by the commissioners forWestminster, with the large end downwards, which is certainly not the right position eitherfor strength or utility; with the small end downwards, and carefully constructed, therewould be less chance of compression or of the sides becoming foul.

Cast-iron inverts, bedded in lengths, are often used wdiere the foundations are sandy or ofa loose nature; they contain 8 or 9 feet superficial, are well adapted to take an extendedbearing, and sustain the brickwork put upon them.

The outlets of many of the sewers which discharge into the Thames are protectedby self-acting valves, which exclude the tidal water, and, in some instances, pen-stocks,under the direction and management of a resident attendant, are added, for still greatersecurity.

Supply of towns with water _The historian Stow most justly considered that, after the

requisite arrangements for the defence of a city, the next subject requiring attention was aplentiful supply of good and wholesome water ; and it appears that London , at the time ofthe Conquest, and for 200 years afterwards, received its water from the Thames , from theriver of the Wells on the west, the stream which ran through Walbrook, and anotherthrough the ward of Langbourn, on the east. The suburbs were supplied by the Old-bourne, which fell into a stream called Wells , and numerous common wells, as the Holy,Clements, Clarks, Skinners, Fags, Tode, Loder, and Rads, well. In West Smithfield wasa . sheet of water called Horse Pool, and numerous wells were scattered over other dis-tricts.

These various streams and wells were constantly cleansed by the authorities of the cityof London, but not being sufficient for the uses of the inhabitants, Henry III . granted tothe citizens and their successors the liberty to convey water from the town of Tyburn tothe city by pipes made of lead : and the first leaden cistern, built round with stone, calledthe Great Conduit in Westcheap, was erected in the year 1285; the whole length of leadenpipe then laid down from Paddington to the cross in Cheap was 1096 rods.

In the year 1401 a cistern was formed at Cornhill, and 22 years after bosses of waterwere made at Billingsgate, near Pauls Wharf; about 10 years after, Newgate and Ludgategaols were supplied. Other conduits were afterwards established, at the expense of thecity, and numerous leaden pipes Laid down. These were annually visited by the LordMayor and wardens of the twelve companies; “they hunted the hare and dined at the headof the Conduit, and after dinner they hunted the fox, finishing the day with blowing of hornsand merry-making.”

A great portion of the citizens had, however, no other means of procuring this importantarticle cf domestic comfort than by fetching it from the Thames by the lanes that leddown to the water-side. These lanes, in the course of time, were walled up at the end bythose who occupied dwellings near, which became so great a grievance that an inquisitionwas established; several presentments were made by persons appointed out of the wards toinquire into the matter, and the evil complained of was considerably abated.

In the year 1582, Peter Morice, a Dutchman, showed the citizens that he could, “ withpipes of lead and a most artificial forcier, standing near London Bridge , convey water intomen’s houses.” This “forcier” is described by Stow as the first mill made to supplythe city with Thames water, and he adds that it remained a long time the property of aMr. Morice.” The houses in and about Gracechurch Street were the first benefited bythis “ new device," and the water was remarkable for its clearness. Six years afterwards,Bevis Bulman set up another forcier near Broken Wharf, and conveyed the water to theneighbouring houses. In the year 1610, pipes of wood and stone were laid down byThomas Hayes, to supply Thames water to the conduit at Aldersgate.

Such were the only means adopted for the supplying water to the metropolis until theyear 1608, when Mr. Middleton commenced his important work of bringing the New Riverfrom Chadwell and Amwell to Islington . Stow tells us that whilst the w’ork was in pro-gress, he frequently, by favour of the owner, did divers times ride and see it, and diligentlyobserved that admirable art, pains, and industry were bestowed for the passage of it, byreason that all the grounds were not of a like nature, some being oozy and very muddy,others again as stiff, craggy, and stony. The depth of the trench in some places descendedfull 30 feet, if not more, whereas in other places it required a sprightful art again to mountit over the valley, in a trough between a couple of hills, and the trough all the while borneup by wooden arches, some of them fixed in the ground very deep, and rising in height