Such, compendiously stated, are the general principles which should guide us in the choice of a water source for any town, in any part of the world. They are amply borne out by practical experience, and have already led the municipal authorities in many parts of this island-especially in Lancashire and Scotland -to abandon the old sources of supply, and to adopt in their stead the new system of Gathering-grounds. Edinburgh and Paisley, Bolton, Bury, and Stockport, are examples of towns already supplied wholly or partly on the gathering ground plan. Liverpool and Manchester have at this moment extensive gatheringgrounds in preparation. On every acre of our sandy heaths fall annually from 2000 to 4000 tons of rain water, and about 500 tons of dew;* of which, allowing largely for evaporation and waste, at least one-third may generally be collected for use. The average annual number of rain days in our climate is 152; and their distribution throughout the year leaves rainless intervals, against which it is necessary to provide by the construction of storage-reservoirs, adequate to contain, as a minimum, sixty days' supply; to which considerable addition should be made to meet the contingency of protracted drought, and to save the water of occasional floods.

nical coagulation) a considerable portion of any organic impurity which may happen to be in suspension. The chalk thus precipitated may be burnt to lime in the usual way; and this very lime may be employed for the purification of another mass of water. One cannot but admire the ingenuity of this chemical artifice (at first sight almost paradoxical), which frees water from lime in one form by the addition of lime in another; and which obliges the precipitated impurities of the first waters treated to throw down the dissolved impurities of succeeding masses. This process, to which the London Water Companies have obstinately refused a trial, has within the last few weeks been brought into operation on a large scale at the Mayfield print-works, Manchester, where, we are informed, its success has proved complete. Mr. Way's sugges tion for softening and purifying water by filtration through loam or clay, though it has not yet been tried on a large scale, is based on sound experiments, and will in all probability lead to valuable practical results. Mr. Cross proposes to free water from certain of its organic impurities by the galvanic action of zinc and iron plates plunged into it; and his laboratory experiments have certainly been attended with a sufficient degree of success to deserve repetition on a large scale. Dr. Hales' plan was proposed more than half a century ago, and is described in Dr. Black's Lectures, vol. i., p. 297. It consists in blowing air through water in small streams, by means of an instrument resembling a bellows, fitted with a long tube, reaching to the bottom of the water, and ending in a perforated streamer, like the rose of a garden watering-pot. This process resembles in its effect the Chinese plan of aërating water by beating it with bamboos; and it is also analogous to Sir John Sinclair's method of impregnating water with air by a sort of churning machine. A mechanism resembling Dr. Hales', but worked by steam power, is employed to drive air through palm-oil, for the purpose of bleaching it (by oxydising its colouring organic matter), which it accomplishes very effectually and there is no doubt that cisterned water, by like aërating agitation, would be freed from the evils of stagnancy, and assume the characters of running

water.

*The dew, caused, as it is, by the condensation by night of vapours raised from the earth during the day, must be reckoned, not as a direct addition to the rainfall, but as an abatement (and a very large one) of the loss caused by evaporation.

It is on the great extent and alleged costliness of these receptacles, and on the assumed liability of stored water to heating and vegetation, that the opponents of gathering-grounds rely for their principal objections to the system. It is found, however, in practice, that by taking advantage of the natural undulations of the ground, large reservoirs may generally be formed at comparatively small cost; and experience also shows that, though vegetation takes place in shallow reservoirs, it is obviated by deep storage, which preserves the mass of the water shaded and cool. By a storage depth of from 30 to 50 feet the gathering-ground water now distributed to part of Glasgow and Paisley, in lieu of the water formerly obtained from the river Clyde, is preserved during the season of drought in unimpaired freshness and purity, and its substitution for the old supplies is esteemed a great boon by the inhabitants. The bleachers declare that it saves them half their expenditure in soap; the tea-drinkers that it makes their tea go nearly twice as far-and the laundresses that it improves the colour, and diminishes the wear and tear of the linen they wash. In considering the question of cost, we shall find that these are elements which count, not for thousands merely, but actually for millions sterling, in the annual expenditure of urban populations.*

The washing bills of the metropolis, estimated at the low average of 1s. per head per week, amount to upwards of 5,000,0007. per annum. A working-man's calico shirt, costing 2s., and washed forty times, at 3d., has five times its original value expended on it, in soap and laundry labour, before it is worn out: a like proportion holds in the costlier washing of more expensive articles. So far therefore as the home market is concerned, the Washerwoman's interest actually exceeds, in pecuniary magnitude, the gigantic Cotton interest itself. Of this washing expenditure nearly onetenth, or half a million sterling, is laid out in soap and soda :-9600 tons and upwards of the former, with 3000 tons of the latter, at 451. and 101. per ton respectively, being used annually in London. From the experience of Glasgow and Bolton, where softwater supplies have recently been introduced, it appears that our London outlay on soap and soda might be reduced at least one-half (i. e. 250,000l. per annum) by substituting a softer water for our present hard supplies: while a still greater saving would result from the diminished wear and tear of the linen itself during ablution, and the proportionately abated toil of the laundress. It is indeed alleged, in opposition to these views (which have been ably set forth by the Board of Health in their recent Report), that half an hour's boiling before use would soften the washerwoman's water, by precipitating a large proportion of the chalk; and that a halfpenny-worth of carbonate of soda, judiciously applied, would neutralize the hardness of 100 gallons of Thames or New River water. But these propositions, though true, leave the practical objection to hard water supplies untouched. For, in point of fact, the washerwomen do not soften their water by boiling it beforehand, nor do they nicely adjust the soda they throw in to the quantity of lime requiring neutralization. On the contrary, the boiling, as they conduct it, throws down the hardening chalk of the water as a gritty precipitate upon the linen washed; while the soda, used by them in excess to diminish their toil, still further deteriorates the fabric by its caustic alkaline property. In deciding social questions of this kind we must take men and things as we find them; considering not what might be, but what is; and protecting the population, so far as we are able, against the consequences of their own ignorance and neglect. 2 K 2

Nor

Nor is the Gathering-ground system, while thus sanctioned by modern theory and practice, less conformable with the indications of foregone experience. It is a logical step in that series of improvements by which the hydraulic engineer has progressively extended his control over water-removing it, at each successive advance, more and more from the operation of chance, i. e. from the casual influx of natural or artificial pollutions. The natural mud-banked streams were long ago replaced by artificial watercourses, lined with stone or brick; next, these were covered in, or replaced by earthen or metallic tubes; and then came Peter Morrys, who prolonged these tubes by ramifying ducts into our very houses. Evidently, a similar extension remains to be accomplished at the opposite end of the aqueduct; and ramifying feeders for gathering water come next in the order of sequence to ramifying ducts for its delivery. As aqueducts are artificial rivers, so, by the strictest parity, these feeders are artificial springs. Constructed at small cost of ordinary clay drainpipes, laid in the usual manner three or four feet deep, they catch the filtered rain-water at its point of maximum purity, and convey it to its destination in channels equivalent for purity to the fissures of the granite rock. Thus the only remaining element of uncertainty-the random flow of water over or through the soilis eliminated; and its whole course, from the ground on which it falls to the tap at which it is consumed, is brought under our direct control. Lands hitherto regarded as profitless wastes, when considered in this new light, spring into sudden value and significance as water-farms, adapted to afford us drink, by those very conditions of sterility which unfit them to produce us food. And, as the richest soil of Europe has for centuries been devoted to the production of beer and wine, so now our barren commons are found available for the supply of that still more inestimable benefit-pure, soft, and wholesome water.

Passing now from these general considerations to the particular case of London, and examining, in the light of the foregoing theory, the local conditions, hydrographic and geological, of the Metropolitan district, the first thing that strikes us is the existence of a range of sandy heaths and moors, stretching north and south from Bagshot to Haslemere, east and west from Farnham to Woking, and covering an area of about 100 square miles, which catch at least 2200 tons per acre per annum of water, for the most part analogous in quality to that already collected and used at Farnham. Lying, as they do, at a mean distance of thirty miles from London, within convenient aqueduct-reach, yet not so near as to be exposed to contamination by the metropolitan soot and ash, these moorlands seem, primâ facie, admirably adapted to

supply

supply water on the new system to the metropolis. A large proportion of these moors, no doubt, are covered with peat, which in times of flood colours the surface-water. But the organic matter thus dissolved is entirely removed, along with that washed down from the air, by percolation through the sand beneath; so that when the brooks on the surface are coloured like tea, the sub-soil drain-streams run brilliantly clear. The peat, moreover, is stated to be so thin, that it might be easily and economically pared off; the value of the product reimbursing the cost of its removal, which would leave a gathering surface of bare sand, washed clean by the rainfall of ages. Some portions of these sands, it is true, have a dark colour, indicating the presence of iron; and the water at a few of these points is said to be slightly chalybeate. But these iron sands are reported to be of limited extent; at least 70 square miles of the district hitherto examined yielding water perfectly free from iron, and as soft as the water of the finest Lancashire gathering-grounds. So far therefore as the able investigations of the Board of Health (to which we owe much of our information on this subject) have hitherto gone, they promise London a water-supply from these new sources, in quantity abundantly sufficient for the wants of the population, domestic, sanitary, and industrial, and of quality superior to that enjoyed by any other metropolis in the world.

While, therefore, we reserve, till fuller information is before us, our final judgment on this important question, we do not hesitate to take the initiative in directing public attention to these artificial spring grounds, as likely to afford us a better supply than any of the sources hitherto proposed. Of these last-mentioned sources, our limits forbid us at present to speak at much length. They all, as we shall hereafter more fully explain, fall under one or other of two main divisions, viz., river sources and spring sources, each of which is further divisible into two sub-groups. Thus under the head of river schemes are included, 1, Thames schemes-for taking the Thames water at Twickenham, Teddington, Staines, Henley, Mapledurham, and various other points from Kew upwards; and, 2, Thamestributary schemes such as the Medway scheme,-Telford's Colne and Wandle scheme, &c. Under the head of spring schemes, in like manner, are comprised, 1, the deep-spring projects, such as that of Mr. Tabberner for raising water from the valley of the chalk basin under London; and, 2, the shallowspring projects, such as that of Mr. Homersham, for pumping water from the outcrop of the London chalk at Watford. Apart from these schemes, yet connected with all of them as means of improving crude spring and river waters, stand the processes of

Messrs.

Messrs. Clarke, Cross, and Way, already referred to, and other purifying schemes, which we shall take an early occasion to pass in review. In the mean time we enter our protest, on behalf of the public, against the adoption, for our future metropolitan supply, of any water contaminated either with earthy salts (like that from Watford), or with alkaline salts (like the Artesian water), or with both mineral and organic impurities (like the water of the Thames and its tributaries), until experiments and trial-works, in conformity with the recommendations of the Board of Health, shall have determined the capabilities of the Surrey and Hampshire

moors as METROPOLITAN GATHERING-GROUNDS.

ART. VII.-Histoire du Gouvernement Provisoire. Par M. Elias Regnault, ancien Chef du Cabinet du Ministre Provisoire de l'Intérieur. 8vo. Paris, 1850.

M. the me,

REGNAULT is one of the many persons attached to

whom the February Revolution suddenly called from obscurity to a prominent official station; and it is natural that his view, both of the Revolution and of the Provisional Government--especially that section of it to which his friend and patron M. Ledru-Rollin belonged-should be highly favourable. Calumny,' he says, 'has long enough misrepresented the members of the Provisional Government :-it is time that truth and justice should be heard in their defence.' We will not deny that M. Regnault writes with more moderation and good sense than we have found in any of his party, nor that his statements have more of 'truth and justice' than we expected from a professed apologist of M. Ledru-Rollin; but we differ essentially from the conclusion that M. Regnault draws in favour of his heroes: for, though he denies several of the lower personal delinquencies imputed to those heroes, we cannot say that he quite disproves them-while he leaves their public character certainly no better than it was, and indeed gives us some fresh insight into the dessous des cartes, which confirms, and sometimes in a very remarkable way, the views of both the men and their motives which we had in former articles opened to our readers. The book is written in a lively and agreeable style, and has, as we are not surprised to hear, had very considerable success. We cannot, however, afford room for more than some of the personal and anecdotical traits verified by this very near observer and, on the whole, candid narrator.

He begins by an historical dissertation on the Reform Ban

quets