1841.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



or stniineJ when llie valves are full open, a very small increase of the 

 speed of the machine will cause the valves completely to cover the 

 ends of the jet-pipes, and when the ends of these pipes are closed, the 

 vater can have no power to turn the machine. From this it will be 

 clear, that the niachiiie can be made so that, when if is doing very 

 little work, it will not move at a much greater speed than it will when 

 acting with its greatest power. 



The new water-mill acts on a principle similar to that of the well- 

 known Barker's mill ; but the arms are bent and otherwise shaped, so 

 as to allow the water to run from the centre to the extremity of the 

 arms when they are in motion, in a straight line, or nearly so, and in 

 this way the disadvantages of carrying the water round with the arms, 

 as is the case in Barker's mill, are got rid of. 



The curve of the arms is such as to allow the water to run from 

 their centres out of the jet-pipes, w ilhout being carried round by the 

 machine, when it is in motion at its best speed. On this account, the 

 rotary motion of the arms will not give to the water a centrifugal 

 force. So the forces which work the new water-mill are simply the 

 force of reaction, and the weight of a column of water of the same 

 height as that acting on the mill, having the area of its cross section 

 eqnal to the sum of the cross-sectional area of each jet-pipe. When 

 the machine is standing, the one of these forces is as great as the 

 other ; but when it revolves so quick that the centres of the jet-pipes 

 move at the same speed as that of the water flowing from them, the 

 force of reaction ceases, as then the water falls from the jet-pipes 

 without any motion, in a horizontal direction, for the machine leaves 

 the water as fast as the acting column can follow it. When the re- 

 sistance to be overcome is as great as will balance tlie force caused by 

 the weight of the water, there is still the force of reaction left to bring 

 up the speed of the machine ; and as the weight of the water remains 

 the same, whether the niachine is in motion or at rest, the force of 

 reaction will cairy up the speed till the centres of the jet-|.>ipes re- 

 volve at a velocity the same as that of the water issuing from them 

 before it ceases. Thus the machine, when its jet-pipes revolve at a 

 speed as great as that of the water issuing from them, will give its 

 maximum of eft'ect, which maximum will be equal to the whole power 

 of the water it uses ; for, in the time a given weight of water is ex- 

 pended, in the same time the machine is able to raise as great a 

 weight from the level of the centres of the jet-pipes to the level of 

 the surface of the water in the lead. There is of course a small part 

 of the power lost, most of which is that caused by the resistance 

 which the water meets with in passing through the main pipe and the 

 machine. This portion of the force is very inconsiderable, as will be 

 shown in the next paragraph; and, by making a slight alteration on 

 some parts of the machine, this small fraction of loss may be still 

 farther diminished. 



A machine erected lalely for Messrs. Xeill, Fleming, and Reid, at 

 their vvorks, Shaws-wafer, Greenock, gives, when tested by the fric- 

 tion apparatus invented by M. Frony, 75 per cent, of the whole jtower 

 of the water w hich works it. The power of the water is 79 horses, and 

 the power of the machine is eqnal to that of !)'3-25 horses or 75 per 

 cent, as now stated. Mr. Stirrat's water-mill of 25 horses' power is 

 the first that was made ; it was tested in the same way as the above- 

 mentioned machine, and the result of the experiment was equally 

 favourable. 



The following are some of the advantages which the hydraulic ma- 

 chine of Messrs. Whitelaw and Stirrat, has over an overshot water- 

 wheel of the best construction. Tiie new mill has a governing appa- 

 ratus, which renders its motion as uniform as that of the best con- 

 structed steam-engine ; when a part, or even the whole, of the ma- 

 chinery which it works, is thrown off at once, the variation in the 

 speed is scarcely perceptible. The speed of the new machine is well 

 suited for every purpose: generally speaking, it can be formed to 

 make the required number of turns in a given time, and on this ac- 

 count, intermediate gearing is done away with. There is little wear 

 and tear on the paits of the new mill, for its weight is perfectly balanced 

 by that of the water, thus taking away almost all friction, and conse- 

 quently wear, at the rubbing parts : five of these machines are already 

 in operation, and not a workman has been employed in any way at 

 either of them since they were first set a-going, although one has been 

 in constant use for nearly two years. The new machine takes up re- 

 markably little room. No very expensive building or other erection 

 is needed for the fixing of the new water-mill, and the cost of the ma- 

 chine itself is very trifling in every case, and especially on a high fall, 

 ■where an overshot wheel, as also the building and excavation recpiired 

 for it, become enormously expensive. On a fall of very great height, 

 where to erect an ordinary water-wheel would be altogether out of the 

 question, the new water-wheel may be employed to great advantage. 

 'I'he new machine may easily be made to ri^e or fall according as the 

 water in the tail-race is high or low, and one form of it will work to 



very considerable advantage in tail-water. The best constructed over- 

 shot water-wheel will not, after the speed is brought up for ordinary 

 purposes, give more than 70 per cent, of the whole power of the water 

 which works it ; and the new machine, as has already been shown, 

 gives 75 per cent., and it can be formed to give even a greater portion 

 of the power of the water than this. 



SUPPLY OF WATER TO THE METROPOLIS. 



It is always with much pleasure that we approach this question, in- 

 teresting as it is not only to the profession, but also to the public at 

 large, being one of those subjects on which both parties meet as oii 

 common ground. The supply of water to the population has always 

 with the supply of food generally acquired great political importance, 

 and the provision for it has called forth some of the greatest triumph,* 

 of engineering. It has been but too truly staled by Dr. SouthwooiJ 

 Smith, in his able Reports on the Health of the Metropolis, that an iu- 

 suflicient or impure supply of water is one of the main causes of dis- 

 ease in all classes of the community, and the means of removing 

 which are well known to be in existence. 



The valuable report which we now lay before our readers, prove* 

 most clearly to every unbiassed mind that London may be supplied 

 with pure water without having recourse either to the "IThames, or to 

 any other river. AU rivers and open canals are infected in some de- 

 gree with vegetable and animal matter, irarticularly after heavy rains — 

 for instance, even the New River is the receptacle of the land drain- 

 age for many miles. The water-works which derive their supply 

 from the Thames are all within the range of the tide, impregnated 

 as it is with the drainage of the metropolis, and the large manufac- 

 tories on its banks, and so must it always be. The works which stand 

 the farthest up the river, those of the Grand Junction Company at the 

 London end of Brentford, are within the immediate vicinity of large gas 

 works, a soap manufactorv, and the drainage of a brewery, and of one 

 of the largest distilleries, without reckoning the drainage of the w hole 

 town. 



'J'o the Provisional Committee of the London and IVeslminster Watcr-V.'orks, 



A.-C. i,-C. 



Gentlemen — The ir.sufticleucy and baduess of the present supply of water 

 to the metropolis have long engaged the public atteutiou ; but although 

 many endeavours have been made to establish it on a better basis, owing to 

 causes which we must seek in the elements of the projects themselves, they 

 have invariably failed. 



.Vb it appears, however, generally admitted, that sometliiiig siiould be done,. 

 we are naturally led to inquire into the reasons of the want of success of 

 former attempts, and by carefully avoiding these, and at the same time en- 

 deavouring to ]>resent an effective and practical remedy, we may still hope to 

 deserve the public confidence. It will, therefore, be my endeavour to show, 

 in the following report, that Nature has suppUed us with the means of sub- 

 stituting a pure and unceasing flow of spring water for the outpourings of 

 filthy drains, and that this can be done without encountering difficulties of 

 any but an ordinary nature. 



Nevertheless, l)efore I proceed to do this, it may not he useless that I 

 should briefly enumerate the various ])lans which have hitherto been sug- 

 gested to attain this object ; as this will at once prove how much time and 

 attention, not only numerous private individuals, but even the legislature, 

 have bestowed on the subject ; and will also enable me to point out to you 

 what appear to me to liave been the causes of their rejection. 



So far back as the year 1821, a committee of the House of Commons made 

 a long rei)ort, in which they recommended that a bill should be passed to 

 regulate the water companies, which had at that time caused much dissatis- 

 faction, on account of the great increase, which a coalition enabled tliem to 

 make, on their former rates. The inquiry, although it does not appear to 

 ha\e led to any positive result, nevertheless, called the attention of the pub- 

 lic to various facts which were not previously generally known, and among 

 others, to the very inferior cpiality of water which many of the companies- 

 snpplied. We accordbigly find, that in 182t, a highly respectable body of 

 gentlemen held a meeting, to take into consideration a proposition of Mr. 

 Philip Taylor's, to conduct the water of the Thames, by means of a subtei'- 

 raneous aqueduct, from a point near Richmond, to reservoirs at Kensal Green 

 and Hampstead Heath. 



In 1825, a company was formed to supply the metropolis with spring 

 water, from beneath the Ijondos clay, a project which was agaiu brought for- 

 ward in 1S35, and to which I shall have occasion, in a later peiiod of this 

 Report, to allude at sonie length. 



But it was not until the spring of 1827 that in consequence of the publica- 

 tion of a pamphlet, entitled " The Dolphin," by Mr. Wright, the general mass 

 of the inhabitants of London could be said to have been aroused to a sense of 

 the paramount importance of a better supply of water to their houses, than 

 that derived from some of the ;nost fou! portions of tltc river Thames. A! 



