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Larcon, which, restricted as it necessarily is, still shows enough to enable us to appreciate the character of that amiable man. The first, second, sixth and seventh papers are on subjects purely military, which prevents us, on the present occasion, from making any comment upon them. The third paper, by Lieut. Nelson, It. E., is on the important sub ject of shot furnaces, a question in the consideration of wdlieh the con struction of iron steam vessels should also enter. In this paper we are glad to see an acknowledgment of the valuable suggestions of Sir John Guest and Mr. Evans. Lieut. Caffin’s description of a new steam apparatus for drying gun powder, shows that he has introduced an important improvement, which we trust will be adopted by the authorities. The memoranda on blasting rock, by Major General Sir J. F. Bur- goyne, form a work, and a most valuable one, in themselves ; we cor dially recommend them to the attention of our engineering readers of every department. Major Harry Jones’s paper, the eighth, gives an account of the well in Fort Regent, Jersey, a u'ork of great difficulty and great success. Major Jones also gives his personal testimony to having witnessed the successful operation of the water finders with the baguette divinatoire. It is curious, but we do not know wbat to say to it. Captain Brandreth’s report cn the Island of Ascension is valuable and interesting, but does not fall within the scope of our observations. The tenth paper is by Major Bolton, R. E., and is descriptive of the dam constructed across the waste channel at Long Island, on the Ri- deau Canal. To this we may afterwards have occasion to refer. Lieutenant Nelson has contributed a series of notes which he calls engineering details, a memoir which must be useful, both as an ex ample and a lesson to the younger members of his corps. The description of the New Victualling Establishment at Devon- port bears ample testimony to the ability of the two Rennies, under whose direction many of the works have been executed. It will be seen, by other examples, that the civil engineer has full attention paid to him in this work. Mr. Howlett, the. chief draughtsman of the Ordnance, describes an ingenious plan of his for connecting a locomotive engine and tender to a passenger train, in which we only see one difficulty—how it would work on sharp curves. Lieut. Denison, the able editor, is author of the fourteenth paper, on a new weigh bridge, lately erected at Woolwich Dockyard, and also of the next, containing an account of another new work in the same establishment, a single coffer-dam. The sixteenth and seventeenth papers on injecting cemeut into leaky joints of masonry, and on the employment of sand for foundations, are translations from the French. The eighteenth paper is on the rolling bridge at Fort Regent, Jersey. The nineteenth paper brings us again to a contribution of the editor, describing the mode adopted for restoring the roof of Woolwich Dockyard Chapel, on the failure of the principals. The twentieth paper is on the wharf cranes made by the Butterley Company, communicated by Joseph Glynn, Esq., F. R. S., and the twenty-first on Mr. Woodhouse’s cast iron bridge over the River Trent, at Savvley, on the Midland Counties Railway. Reports, Specifications and Estimates of Public Works of the United States of America. Edited by W. Strickland, Architect, C. E.; Edward H. Gill, C. E.; and H. R. Campbell, C. E. London: John Weale, 1841. W T hen the “ Public Works of England ” first appeared, we expressed our approbation of the superior manner in which Mr. Weale had brought out that valuable work, an opinion which was fully borne out by the countenance of the public, and the satisfaction of the profession. It is at once a proof and a result of the success of Mr. Weale’s exer tions, that our Transatlantic brethren have entrusted to his care a similar volume on the Public Works of America. It affords us double pleasure to see that they have commenced so well, and that they have taken such an effective step to do justice to their works. The present is a companion to the former work, and is fully equal to it, it shows the same careful selection of subjects, the same fulness of details, and the same splendour of execution. We have no doubt of its success with the profession, for every exertion has been made to deserve it, and it has our heartiest wishes, not less for its intrinsic merits than for the good it is calculated to do the profession. We know nothing better adapted to promote professional studies, and to elevate the character of such pursuits among the public, than the productions of works like these, which are the best monument to the old practitioner, and the best lesson to the beginner. This, we are sure, is but part of a series, for the success of the result we trust will embolden Mr. Weale to give us also the Public Works of the Continent, and thus lay the foundation of a museum of practical information, to which every department of the profession may have recourse. We shall now proceed to detail the contents of the first two parts of the work before us. The first 13 plates represent the Phila delphia Gas Works, constructed in 1835, under the direction of Mr. Merrick; the following extracts will show their extent: The works are laid out in eight distinct sections of ten “ benches,” or thirty retorts each, making an aggregate of two hundred and forty retorts. Each bench yields upon an average 10,000 cubic feet of gas daily, or, when in full action, an aggregate of 800,000 feet. To each section is a distinct washer, purifier, condenser, and station meter. The two retort-houses are each 200 feet long and 50 feet wide, located in the centre of the square, having between them a passage of 40 feet, which is ex cavated as a cellar and floored over water-tight. This passage and the arched cellars under the retort-houses serve as coal stores. Each retort-house contains one stack and four sections of retort benches, built back to back down the centre of the building on each side of the chim ney. The apparatus for cleansing the gas is located to the north and south of each retort-house respectively. Two sections of retort benches are now completed and in action, and a third is now in the course of erection. The retorts are the broad or York D’s, 20 inches by feet in the clear, set upon an original plan. The gas is washed in two waters through washers of simple construction, with valves so arranged as to use either as the first, the most pure water being used as the seeond. The condensers are of ordinary construction, modified so as to enlarge the receptacle for the residuum at the base of the columns. The purifiers are constructed for dry lime, with a hydraulic seal for shifting, by which the use of valves in the purifying house is avoided. After passing the meters, the gas from all the sections mingles in the gaso meters or gas-holders. Appended to the description of the Gas Works there are some valu able reports upon the construction of the works, the cost of making gas, &c. The next plate is a drawing of a Reservoir Dam across the Swatara. Plates 15 and Hi exhibit the construction of the Twin Locks on the Schuylkill Canal at Plymouth (U. S.) Plates 17 & 18 the bay of Delaware and the Breakwater in progress; the following extract from the report describes its magnitude; after examining into the con struction of the Breakwaters at Cherbourg and Plymouth, the report recommends ; The inward slope at 45°, the top 30 feet in breadth, and at 5^ feet above the highest spring-tide ; the outward slope of 39 feet altitude, and of 105J feet base; both dimensions measured in relation to a horizontal plane passing by a point taken at 27 feet below the lowest spring-tide. The base bears to the altitude nearly the same ratio as similar lines in the profiles of Plymouth and Cherbourg Breakwaters. The part comprehended between the sea bottom and a horizontal plane G feet below the lowest spring-tide, the mass to be formed of stones weighing from f to 2 tons, those of 2 tons comprising three-fourths of the mass. The slopes of this part to be covered with blocks weighing from 2 to 3 tons. For the part comprised between the latter horizontal plane and the lowest spring-tide, the mass to be composed of stones weighing from £ to 2J tons ; those of 1J to 2J tons forming three-fourths of the mass. The slope of this part to be protected by blocks weighing 3 tons. For the part comprehended between the lowest and highest spring-tide, the mass to be formed of blocks weighing from 4 to 5 tons, and laid as regularly as practicable. The slopes of this part to be formed of the largest blocks and to be laid headwise. The estimate submitted by the Board was as follows :—The profile of the work rests on a bottom of 29yL feet, on an average, below the lowest spring- tide, and has a superficies of 535,472 square yards; which, being multiplied by 1700 yards (the whole length of the work), gives for the capacity of the mass 910,302-jiy cubic yards. Plates 19 to 24 exhibit the construction of the Philadelphia Water Works, the following description will give an idea of their ex tent :— It has been from the commencement determined, for the present, to erect only three wheels and pumps, which are now completed, (there are now six), and with them the most important part of the duty of the Committee. The first of the wheels is 15 feet diameter and 15 feet long, working under 1 foot head and 7 feet fall. This was put in operation on the 1st of July, 1822, and it raises If million gallons of water to the reservoir in twenty-four hours, with a stroke of the pump of 41 feet, a diameter of 16 inches, and the wheel making 11 revolutions in a minute. The second wheel was put in operation on the 14tli of September, 1822, and is the same length as the first, and 1G feet diameter; it works under 1 foot head and 71 feet fall, making 13 revo-