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1839.] 107 THE CIVIL ENGINEER AND ARCHITECTS JOURNAL composition of most of the cements and mortars used in this country, so as to give the architect and engineer much useful information. In this appendix the Colonel lias given a description of Mr. Brunei’s experi mental brick arch, the dimensions and details of which he states that he has derived chiefly from the sixth number of this journal. This account he believes to he correct, except that nett cement was used instead of mortar, composed of cement and sand, as stated by us. In consequence of this correction by the Colonel, we again made enquiries of the brick layer who assisted in the construction of the arch, and who still persists that cement and sand were used, and not nett cement; we have also procured a piece of the brickwork from the arch, and we feel bound to state that from its appearance it seems to be constructed of nettcement. We do not think it necessary to say anything further in praise of this work, for we feel assured that the extracts which we have given from it are sufficient to convince our readers of its highly valuable and prac tical nature. It is, in fact, a work which every member of the pro fession may refer to with advantage,as he may place every reliance upon the correctness of the experiments which are there detailed. Life of Thomas Telford, written by Himself. Ldited by John Rickman. London : Payne and Foss, 1838. We have purposely delayed our notice of this work, that we might not be accused of not paying due attention to it, or hastily passing a judgment unfavourable to its claims. It is a work which was anxiously awaited by the profession, and naturally looked for as a great ac cession to the stores of scientific literature, but we regret that its appearance has deceived these expectations. The “Life of Telford,” described by his works, offered a field which, in judicious hands, could not fail to have produced a book of standard reputation. The price also, of eight guineas, demanded for the present volume, and the circumstance of funds having been provided for its execution by Telford himself, is so high, as to require great exertions to justify such a charge, and we vainly hoped that, from among the papers of Telford, many valuable ideas would thus have acquired a greater circulation. A large volume of plates is certainly given, but they contain so much that is trite, and so much that is useless, that they greatly derogate from the value of the mass. The work has been thrown into the form of a narrative, under I he plea of insuring greater ease and freedom, but the subject has been so mutilated by the editor, that it is neither an autobiography nor anything else. The few snatches of Telford that are left, give a promise of what he was capable of effecting; and we should have derived an invaluable example in the relation of a progress through life, of which he has given us such a modest commencement. Tel ford, however, never lived to finish his work, and his editor has taken such liberties, that if anything of Telford is left, it is principally his faults. He has warped the current of the • subject to make room for irrelevant dissertations; the descrip tions of works, instead of showing the minute care with which an author would dwell on his designs, are derived from the commonest sources, and a considerable part of the work is occupied with parlia mentary reports, superannuated documents, Roman baths, and other men’s works. We deplore this catastrophe, as it is one which we have heard greatly regretted by many members of the profession, and we had certainly expected something better when we looked at other engineering works of less pretensions. The money and repu tation of Telford have been lavished on it, but it shrinks in the scale when compared with such volumes as the “ Public Works of Eng land,” “ Railway Practice,” the reprint of “ Smeaton’s Reports,” or the new edition of “ Tredgold’s Steam Engine any one of which contains far more practical information, at half the cost, than this “splendid work of Telford.” We need scarcely say that the editor has fully redeemed his pledge of “ not requiring classifi cation of subjects,” and that he has produced a most admirable and agreeable confusion. As to the literary portion of the work, which Telford’s diffidence imposed on the editor, it is very scanty and unsa tisfactory; and although we could excuse this from Telford, we can make no concession to the editor. Instead of this work being called the “ Life of Telford, written by himself,” it should be the “ Life of Telford,” with the part of “himself” by Mr. Rickman; and thus the name of Telford would be redeemed from the slur cast on it by this compilation. Altogether, Telford is most singularly unfor tunate, that when, having taken some care to maintain his reputation, he should have confided the task to one so manifestly incompetent. To deny that the w ork has some merit would be absurd; for it would he impossible that Telford could be associated with an enterprise without conferring some lustre on it; but our opinion of the compi lation as a whole is, that neither the quantity of information commu nicated, nor its quality, are at all commensurate with the extent of its assumptions or the magnitude of its price. The drawings of Telford, it is true, are to be found in the library of the Institution of Civil Engineers, but who can find time to study them there ? Few men can afford to sacrifice, in such researches, their leisure and their time. The work commences with a descriptive narrative of the works of Telford, and such short snatches of his life as the editor has left un- pruned. Thomas Telford was an orphan of a working mason in an obscure part of Scotland, and this avowal which his sense of innate dignity prompted stands in solitary contrast with the lack of farther information. We find him successively working at Edinburgh and at Somerset House, then of a sudden superintending works in Ports mouth Dock-yard, and afterwards county surveyor of Shropshire. We see no proof of merit w hich could warrant this rapid rise, and we look in vain to the work for an explanation of the circumstances which thus determined his career in future life. We can appreciate the studious and laborious attention with which he cultivated his mental powers, but we must look to other operations for the causes of his promotion, and we may believe that had it not been for the patronage of his schoolfellow, SirWilliam Johnstone Pulteney, his career might have been in a lower grade, and his reputation of less extent. As county surveyor, we find Telford first engaged as a civil engineer ; and here he had full scope for his favourite pursuit of bridge-building. The first bridge the construction of which lie superintended was one of three arches over the Severn, and soon afterward he constructed the second cast-iron bridge in England, at Buildwas, the first having been at Colebrookdale. This consisted of a single arch of 130 feet span, of which the iron-work was executed, in 1790, by the Cole brookdale Company, by contract with the county magistrates, for 6,0341. 13s. 3d. Of this bridge an engraving is given in the Atlas; and besides these, he erected forty smaller bridges in the county. This led to further employment in the same line, and he also at tempted some works as an architect, though with very little credit to his taste. The parish church of Bridgenorth, in Shropshire, which had been the chapel of a Norman Castle, he rebuilt in a mixture of the Greek and Roman styles. In 1793 we find him engaged in one of his first great works, the Ellesmere Canal, the managing committee of which was principally composed of county magistrates. Telford’s management of this com plicated work was such as fully to justify their confidence in him, and he thus acquired new means of displaying the boldness and originality of his mind. Here we find descriptions of two works of magnitude, the Chirk Aqueduct and that of Pont-y-cysylte. “ The Ceriog, or Cliirk valley, is 710 feet in width; the banks are steep, with a flat alluvial meadow between them, through which the river passes. To preserve the canal level, the surface of its water must be maintained at 65 feet above the meadow, and 70 above the water in the river. There arc 10 arches, cacli of which is 40 feet span. The first stone of this aqueduct was laid on the 17th June, 1796. Previously to this time, such canal aque ducts had been uniformly made to retain the water necessary for navigation, by means of puddled earth retained by masonry; and in order to obtain sufficient breadth for this superstructure, the masonry of the piers, abut ments and arches was of massive strength ; and after all this expense, and every imaginable precaution, the frosts, by swelling the moist puddle, fre quently created fissures, burst the masonry, and suffered the water to es cape, nay, sometimes actually threw down the aqueducts ; instances of this kind having occurred even in the works of the justly celebrated Brindley. It was evident that the increased pressure of the puddled earth was the chief cause of such failures; I therefore had recourse to the following scheme in order to avoid using it. The spnudrills of the stone arches were constructed with longitudinal walls (as at Kirkcudbright Bridge), instead of being filled with earth, and across these the canal bottom was formed by cast-iron plates at each side, infixed in square stone masonry. Those bot tom plates had Handles on their edges, and were secured by nuts and screws at every juncture. The sides of the canal were made waterproof by ashler masonry, backed with hard burnt bricks, laid in Parker’s cement, on the outside of which was rubble stone work, like the rest of the aque duct. The towing-path had a thin bed of' clay under the gravel, and its outer edge was protected by an iron railing. The width of the water-way is 11 feet, of the masonry on each side, 5 feet 6 inches, and the depth of the water hi the canal is 5 feet. “ By this mode of construction the quantity of masonry is much dimi nished, and the iron bottom plate forms a continued tie, and prevents the side walls from separation by lateral pressure id’ the contained water. There being a quarry of excellent fiat bedded rubble-stone within a quarter of a mile of the site, and lime-kilns within two miles, the whole, with the exception of quoins, coping and lining the sides of the water-way, which are of ashler masonry, is of rubble work, laid in lime mortar; the materials and workmanship equally excellent. The edifice was completed in the year 1801, and is still in a perfect state; the total cost was £'J0,898.” * * ***** “ About four miles north of Chirk, the aqueduct of Pont-y-cysylte forms a still more striking object than that which I have just described. The north bank of the river Doe at this place is abrupt; on the south rid; thq