306 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[Atjsust, 



just the same were that space overhead unglazed. Here, then, the 

 liglit comes in immediately from above, while the two vestibules or 

 ends have only what they receive from this centre avenue and from 

 their open entrances. Having pointed out — and with hearty appro- 

 bition — what we consider unusual merits, we shall hardly be thought 

 verv Jnfair and invidious, or disposed to find fault for the nonce, if 

 ve also advert to what is, if not a positive blemish in ihe design 

 itself, some drawback upon it: we allude to the disagreeable and 

 marring effect — to our eyes at least — occasioned by the backs and 

 naked brick walls of the adjoining houses being seen through the sky- 

 light over the centre avenue. If they were not to be kept out of 

 sight by employing either ground or "waved" glass for the skylight, 

 the backs of those houses as belonging ardtilectiirallu to the Change 

 itself, should have been treated accordingly; had which been done, 

 their being seen from below through the skylight would have very 

 greatly enhanced the total effect, and would have been also a novelty 

 in itself. But, unluckily, extraneous circumstances and accidents of 

 the kind are very rarely taken into account in making designs, in doing 

 which it is too readily taken for granted that nothing will be seen but 

 what is actually meant to be seen — as in this instance. 



We have as yet said nothing of what will assuredly strike the ordi- 

 nary spectator — in other words, the public — first and foremost, namely 

 the polychromic decoration, here for the very first time introduced 

 into any place of the kind, except we look upon the Pantheon 

 Bazaar a previous exam|)le of it. In this respect, therefore, New 

 Exeter Change is of quite novel character, and a decided advance 

 upon every other "Arcade." All the more desirable it is that ad- 

 vantage should be taken of such places for applying it, because any 

 decoration of the kind in the open air is almost utterly out of the 

 question in this climate, even were it to be executed in fresco. This 

 specimen of it is, we presume, entirely in distemper (by Mr. Collman), 

 and is sufficiently satisfactory in its general appearance and effect, 

 although, perhaps, some of the ornaments — those on the cove and 

 ceilings — somewhat too minute, or else too scantily supplied. The 

 giving the windows above the shops painted arabesque burderings in 

 the Pompeian style, instead of architectural dressings, is by no means 

 an unhappy idea ; but we are not exactly pleased with the intermediate 

 small arched panels. Square headed ones, either not so much sunk or 

 not sunk at all, would, in our opinion, have better suited the design. 

 It cuuld be wished, too, that some colour or ornament had been be- 

 stowed on the entablatures of the shops. Since that has not been 

 done (at least not yetj, we hope that if intended to be plain they will 

 be kept so, and not now be allowed to be painted according to the 

 fancy of their respective occupiers ; for should that be done, the whole 

 place might just as well have been merely white-washed. 



For the New Exeter we wish as much prosperity and fame as was 

 enjoyed by its predecessor; yet, though we would not have the re- 

 mark taken as one of evil augury, we cannot help entertaining some 

 appreiiension for it as a speculation, on account of its being in a situ- 

 ation where no thoronghlare whatever is required, because merely as 

 such it is no public convenience — except as affording shelter during a 

 shower of rain — for it opens no nearer communication, were any 

 wanted, between Catherine and Wellington Streets, than what is al- 

 ready provided by Exeter Street, almost immediately adjoining. It 

 will of course now quite supersede the last-mentioned street, but then 

 the traffic there is so inconsiderable as not to be worth speculatmg 

 upon. The Change must therefore depend upon its own attractions, 

 and as far as architectural attractions will serve it, Mr. Sydney Smirke 

 lias bestowed on it not a few, and those of no ordinary kind. 



ON THE SUPPLY OF WATER TO TOWNS. 



(Continued from page 282 J 

 Extracts from ihe First Report of the Commissioners for Inquiring into the 

 State of Large Toivns and Populous Districts. 

 Mr. Thomas Wicksteed, C.E., Engineer to the East London Water Works, 

 and als" to the Kent and Vauxhall Water Works, was examined in answer 

 to the following question : " Have you calculated what would be the abstract 

 cost of lifting a certain quantity of water, say 1000 gallons, 100 feet hiyh, 

 supposing the engine set up ami all the establishment fixed ?" Mr. Wick- 

 steed stated, " 1 have gone into those calculations, but each case must have a 

 diflerent calculation. No general rule can be laid down for it. I will take 

 two towns. The town of Hull, where the corporation are going to enlarge 

 their works, having just obtained an Act of Parliament for that purpose. 

 Hull is a very flat town ; the works will be about half a mile from Ihe out- 

 skirls, and the whole supply of water will be raised by steam engines. At 

 present they raise the water about 40 feet : it is proposed to raise it about 

 120 feet above the town. The extent of ibe proposed pipeage will be about 

 40 miles ; the supply will be for about 110,000 or 120,000 inhabitants ; in this 



case the whole of the water must be raised by steam machinery, and having 

 no elevated ground, and having to raise water by mechanical power in a 

 stand-pipe, the head of water is limited to a certain extent, and the head of 

 water being limited, the sizes of the mains must be proportioned to the limited 

 head. Now, in Cork there is a very large river, and ample water-power 

 there, and steam-power will not be required for above si.t weeks out of the 

 twelve months; the cost, therefore, of carrying on these works, as far as the 

 machinery is concerned, will be less. There is also elevated ground close to 

 the city, where it is proposed to erect the water. works 280 feet high. The 

 water can be raised immediately by the natural power of the river to a very 

 great elevation ; and thus the sizes of the pipes w-ill require to be much less 

 than if the elevation were less, so that the estimate for the same work at 

 Hull would be very diflerent from the estimate for the work at Cork ; and in 

 almost every town the circumstances vary. In some cases a supply may be 

 obtained by going a little distance from the town ; the source may be so ele- 

 vated that no machinery will be required to lilt the water. At Kingston, in 

 Jamaica, tliey have within four or five miles a fall of about 600 feci, so that 

 the expense of supplying Kingston will be comparatively very small, as no 

 machinery will be required to raise the water. In fact, in almost every case 

 there must be a variation according to its circumstances.— In my first report 

 to the corporation of Hull I stated, " The annual consumption of coals will 

 be in the following proportion : for 6000 houses, 180 tons ; for 13,000 houses, 

 390 tons; for 20,000 houocs, 600 tons." 



— At the request of the commissioners Mr. Wicksteed prepared the following 

 slalements. 



Cost of Raising Water. 

 1st. A single pumping engine, made by Boulton and Watt in 1809, working lOi hours 

 pel- diem, ti days per week, mean power I'tti horses; quanlily of water raised per 

 diem equal to U 12,360 gallons, lUO leet high; the cost of coals 12s. per ton. In the 

 estimate for the cost all charges for coals, labour, and stores, are included, but no 

 charge for interest upon outlay, or repairs of machinery and buildings; all other 

 charges for working the engine are included. 



8. d. 

 Cost of raising 1000 g.illons 100 feet high . . 0-.i43 



Or, cost of raising 2'-,oyy gallons 100 feet high . . 10' 



This estimate is made upon an average of two'years' working. 

 2nd. Two single pumping engines, made by Boulton and Watt in 1809, worlcing 24 

 hours per diem, 7 days per week, mean power of each engine 30i horses; quantity of 

 water laised per diem 2.922,480 gallons, 90 feet high ; the cost of coals 12s. per ton. 

 Labour, stores, &c. taken as in the lirst case. The estimate made upon an average 

 of 10 years' working. 



s. d. 

 Cost of raising 1000 gallons 100 feet high . . 0-358 



Or, cost of ra'sirig 33,019 gallons Ul feet high . . 10' 



3rd. Two single pumping engines, made by Boulton and Watt, one in 181*5 and one in 

 1828, working 12 houi-» per diem, 7 days per week, mean power of each engine 76 

 horses ; quantity of water raised per diem 3,601,110 gallons, 100 feet high ; cost of 

 coals r.'s. per ton. Labour, stores, &c. as befora. The estimate made upon an aver- 

 age of 10 years' working. 



s. d. 

 Cost of raising 1000 gallons 100 feet high . . 0333 



Or, cost of raising 30,036 gallons lUO feet high . , 10- 



4th. One single pumping engine, made by Harvey and Co., upon the expansive princi- 

 ple, in 183.'', working 24 hours per diem, 7 days per week, mean power 95^ horses; 

 quantity of water raised per diem 4,107,816 gallons, 110 feet high; cost of coals 12s. 

 per ton. Labour and stores as before. The estimate made upon an average of 4 

 years' working. 



3. d. 

 Cost of raising 1000 gallons 100 feet high . . 0-160 



Or, cost of raising 80,000 gallons 100 feet high . . 10- 



The foregoing statements of the cost of raising water with diflerent engines 

 will show that there is a great variation. The comparison, however, is fa- 

 vourable to the engines upon the old plan, as those quoted are good ones. 

 The following table will show the varialion more clearly :— 

 To raise 160,000,000 of gallons of water 100 feet high, it would cost — 

 According to the 1st statement . A'362 



Ditto 2nd ditto . 238 



Ditto 3rd ditto . 222 



Ditto 4th ditto . 100 



Mr. Wicksteed stated that " a very great economy may be introduced by 

 the use of Ihe expansive-engine and plunger-pump, the advantages of which 

 have been felt in the mines of C'orn»all for 30 years or more, although he be- 

 lieves it was not introduced into water- works establishments until the latter 

 end of 1837, w hen an engine upon tliat principle was set to work at the East 

 London Waterworks, and is now working most satisfactorily, having from 

 tlie time of its first starting continued to raise 225 barrels of water with the 

 same quantity of coals that the best engine on the works, made upon the old 

 construction, required (and requires) to raise 100 barrels. Since that time 

 another large engine of the same description has been erected attheSouth- 

 wark Waterworks, whose performance is equally good, if not superior. The 

 comparison above giver, is too much in favour of the old engines and against 

 the new, taken as a class, as there are instances in London, and in the coun- 

 try, where the quantity of water raised by the consumption of a given quan- 

 tity of coals is not more than one-fourth orone-fil'th of tfiat raised by the 

 new engine. There is another way of shewing the advantage to be derived 

 from Ihe introduction of this new engine ; namely, that the same quantity of 

 water may be raised from 2| to five times the height by the consumption of 

 a given quantity of coals ; and as the size of the pipes depends upon the 

 velocity of the water passing through, and as the velocity increases as the 

 square root of the head of water, so by increasing the head of water four 



