ISJT.] 



THE CIVIL ENGINEER AND ARCHITECrS JOURNAL. 



51 



than Smeaton left them, by making them self-regulating as to the extent of 

 the surface of their sails presented to the action of the wind, according to 

 the form and mode invented by Meikle in 1772; by Bywater in 1S04, 

 with an improved mode of clothing the sails ; and still further by our va- 

 luable member, Cubitt, in 1S07, who brought the system to perfection. 

 Smeaton was amongst the first to point out the laws which govern the for- 

 mation and maintenance of harbours ; and, after undertaking a voyage of 

 observation through Holland, he introduced great improvements in the 

 draining of marsh lands (as at Holderness aud the North Level), a subject 

 which had up to that period been very imperfectly understood ; aud, by the 

 design and construction of the celebrated Eddystoue lighthouse in 1755-59, 

 Smeaton introduced a new era in masonry, which forms a brilliant epoch 

 in his valuable life, spent in the service of mankind, but more particulrrly 

 for the benefit of his country. In 1765 Smeaton directed his attention to 

 Newcomen's engine, and construcied a small engine, at his own house at 

 Austhorpe, in order to conduct his experiments and obtain more accurate 

 results in practice. By the judicious improvements which he introduced 

 in the proportions and structure, he diminished materially the consumption 

 of fuel, then an object of paramount importance, and soon after constructed 

 engines on Newcomen's principle, which far exceeded anything of the kind 

 hitherto produced : amongst these may be mentioued the engines at Long 

 Benton, near Newcastle, and at Chasewater, in Cornwall ; he thus render- 

 ed the system of Newcomen as perfect as it could be made. From the im- 

 provements of Smeaton on wind aud water mills, we may date the founda- 

 tion^ of the modern system of manufacturing, and from those in Newco- 

 men's engine the modern system of mining. 



Watt. — In 1730 Watt was born, aud from his early years manifested 

 symptoms of that genius and sagacity wliich, at a later period, enabled him 

 to work out, with wonderful success, those grand discoveries which have 

 immortalized his name. He began his career as a mathematical-instru- 

 ment maker, and subsequently became an engineer. He proposed a plan 

 for improving the river Clyde, and suggested the idea of the Caledonian 

 Canal, but afterwards devoted himself almost exclusively to the improve- 

 ment of the steam engine. His improvements, or rather inventions, may 

 be stated, generally, as follows; — the separate condensing vessel, with an 

 air-pump for exhausting the steam cylinder, instead of injecting cold water 

 into It for impelling the piston on Newcomen's plan, by atmospheric pres- 

 sure; in conjunctiou with Boulton, he brought these improvements into 

 operation about the year 1773, and produced a still greater diminution in 

 the consumption of fuel than Smeaton had done, thus rendering the appli- 

 cation of the steam engine for pumping water much more general. In 

 1781 heinvenied the means of producing rotatory motion by the steam en- 

 gine, first by the crank, and afterwards by the sun and planet wheel, tlias 

 rendering it applicable for the purpose of driving all kinds of machinery, 

 which was a grand step towards the improvement of manufactures. In 

 1777-82 he invented the application of steam, with expansive action and 

 with double action, alternately above and below the piston. In 1784 he 

 invented the parallel motion, or working gear and valves, the governor, and 

 other important details. All these improvements or inventions were carried 

 into effect in an engine made by Boulton and Watt, in 1784, for one of the 

 London breweries, and in 1785 in others for the Albion mills, which were 

 Uie first steam-mills, now become so general ; thus steam power was ren- 

 dered available for working machinery of every kind, by following the best 

 examples of this most wonderful and useful of all machines, which has so 

 deservedly immortalized the nnme of M'att. The account of the extraor- 

 dinary labours and inventions of Watt and his successors is well given by 

 otir valuable member Farey, in bis excellent work on the steam engine, to 

 which I would refer you, and also to the treatises by Tredgold, Arago, 

 ScQtt Russell, aud others. ' 



Brindlei/.— About this period (1716), Brindley, who may be jnstly called 

 the father of inland canal navigation in England, was born. He com- 

 ntenced his career as a millwright, and was withdrawn from that occupa- 

 tion by the Duke of Bridgewater in 1758, for the purpose of executino- his 

 great canal. Pound locks had been introduced long before on river navi- 

 gations, and on the Exeter and Topsham Canal, which was commenced in 

 1581, and terminated about 1695 ; they were also used on the Sankey 

 C^nal m 17.)5, for the purpose of rendering Sankey Brook navigable- 

 \Tliicb was effected by making an almost entirely new channel. Brindley 

 mibsequenlly executed, with great success,the Trent and Mersey, or Grand 

 Iruuk, the Leeds and Liverpool, the Birmingham, the Forth and Clyde 

 canals, in conjunction with Smeaton and several others, with all the neces- 

 sary works belonging to them, which will ever remain as lasting monu- 

 ments of his skill and genins in this valuable department of Civil Engi- 

 neering. At an early period of the reign of George III., the importance°of 

 canal navigation became universally acknowledged as one of the Greatest 

 nreans then known, of facilitating the transport and reducing the'cost of 

 the necessaries and luxuries of life, and thus contributing to the wealth and 

 pixispenty of every part of the kingdom ; those prejudices and obstacles by 

 which, at the ouUet,every great improvement is surrounded, gradually be- 

 gan to give way, canals became popular, and superseded river navigation 

 so much as to call forth the celebrated answer of Brindley to the question 

 What IS the use of rivers ?"-" To supply canals." Engineers who had 

 displayed such abilities in planning aud executing works of the nature 

 above described, began to acquire that importance as a profession which 

 was soon after destined to work such a beneficial change, nay, almost a 

 revolution m society, auj a^celeral^ sij greatly the eivilizatioa of wan- 



l th« 



Smeaton and Brmdley were accompanied and followed by a number of 

 able men in rapid succession ; amongst whom Jessop, Whitworth, Mvlne 

 \eoman, Henshall,Golborne, Huddart, Kennie, Ralph Walker, Chapman' 

 Telford, and others, all stimulated to exertion by the magnificent career be^ 

 fore them, each contributing, more or less according to the.r several oppoc- 

 tunities, great skill and invention of their own, in addition to that acquired 

 from their predecessors. Favoured by the command of great funds (which 

 were rapidly forthcoming as the success of the works already executed be- 

 came manifest), better workmen and materials, new and improved ma- 

 chinery, steam power, and greater induence over the public mind, their 

 operations were conducted upon a scale of magnitude, utility, and import. 



^dvL^^^'^h^""^ ^ °7 ''5"*"='«'- '^ ">« «se i° vvhich they tlourished, and 

 advanced the prosperity of the empire. 



ENGiNEEitiNo Works. 

 C<ina/s.--To attempt to enumerate all the various public works which 

 hen crowded each other in rapid succession, constituting the character of 

 the profession, and entitling it to public confidence, would he both difticuU 

 and tedious; they are well known and duly appreciated, aud it will suflice 

 to point out some of the most important. The Forth and CIvde Canal bv 

 Smeaton, (1768,) length 24 miles, depth 8 feet, locks 19 feet by 75 feet 

 top-width of canal 60 feet ; the EUesmere by Jessop and Telford with its' 

 magnificent aqueduct across the Dee near Llangollen, consisting- of 19 

 arches 40 feet span, the centre being 126 feet above the Dee, with^a total 

 length of 1020 feet, and a width of 12 feet, the piers of stone, and llw 

 arches and aqueduct of cast iron ; the Caledonian Canal by .lessop and 

 lelford, 22 miles long, depth 16 feet, locks 40 feet wide by 172 feet Ions 

 8 feet rise, top-width of canal 110 feet ; locks intended for a depth of 20 

 feet; commenced in 1803, opened October, 1S20 ; the first and last of 

 which, together with the Gloucester and Berkeley Canal, may be cited n 

 the hist upon which sea-borne vessels could navigate, and thus extend th 

 benefits of ship navigation into the interior of the country, without the da- 

 ay and expense of transhipment of cargoes until arriving at the ware- 

 houses whence they are to be distributed. The Grand Junction (Jessop 

 and Whitworth), Lancaster and Kennet and A von (Rennie). On the Lan- 

 caster navigation the canal is carried across the Lune by a stone viaduct 

 of 5 semi-circu ar arches, 75 feet span each ; the total length of viaduct is 

 600 feet and height 55 feet above the river. The Aire and Calder, the 

 Union the Shrewsbury, New Birmingham and Liverpool, Carlisle, the 

 Grand and Royal Canals, Ireland, amongst many others may be quoted as 

 examples of artificial canals for vessels, so as to enable them to continu« 

 their navigation inland from large rivers and estuaries. The total length 

 ol canal navigation now in operation in England, Scotland, and Ireland, 

 amounts to about 3,000 miles. o j , , 



The most advantageous speed for boats on a canal is about 2A miles per 

 hour, at which rate an average horse is capable of drawing about 22 tons 

 without injuring his physical powers; when this is much exceeded, the 

 ratio of resistance approaches the cube of the velocity. The speed must 

 be diminished in proportion, and the horse exerts his powers to great dis- 

 advantage. Large canals, where practicable, on account of the trade and 

 other circumstances, are preferable to small ones, as they are worked more 

 economically. Various contrivances have been made to obviate the neces- 

 sity of locks in overcoming extensive lifts or declivities, amonest these may 

 be mentioned the inclined planes on the Duke of Bridgewater's and the 

 1 aiiiar and Shrewsbury canals. Double locks, side ponds, hydraulic lifts, 

 by Woodfaouse, Salmon, Congreve, Underhill, Green, and others; but es- 

 teusive reservoirs and feeders are indispensable in most districts where 

 there is a great traftic, and steam engines have been extensively used to 

 pump back the water to be used over again in case of deficiency. 



Steam Dredging-— The improvement of the River Clyde, begun by Wm 

 and Golborne, received fresh stimulus under Rennie and Telford, from tire 

 application of steam power to the dredging-raachine by Grimshaw, in 

 li96, and Bentham in 1802; thus forming a new era in the means of in>- 

 proving river navigation and harbours, since which this important depart, 

 ment of engineering has been carried to an extent which could not other- 

 wise have been attempted. Sieamdredgiug machinery is now generally 

 adopted with success, more particularly in rivers where their beds and 

 channe s can be excavated to a certain degree of uniformity, and where 

 the inclination of the tidal and fresh-water currents can be reduced to such 

 an extent, by the removal of obstructions, as will enable them to keep their 

 channels open. As successful examples of this, I need only adduce the 

 Lagan, the Boyne, the Newry, the Litfey, and the Shannon, iu Ireland, 

 the Clyde, the Leith, the Don, in Scotland. The Tyne, the Wear, the 

 lees, the Thames, the Dee, the Ribble, the Severn, and others, in Enj}- 

 land; and as to harbours, most, if not all, of them can be maintained by 

 steam-dredging, in addition to other means, to a greater depth than could 

 be oblaiued without such an important aid. 



Stone Bridges. 

 Westminater Bridge, by Labelve, in 1740 47, may be considered the 

 first example of extensive structures of this kind. It consists of 13 sem»- 

 circular arches (the centre of which is 75 feet span)^ 1164 feet long; it 

 was originally intended for a wooden bridge, aud was partly commenced 

 on this principle ; it was a great work at the time, but as might have b^en 

 expected, contained defects, particularly in the fonndaiions, wliich at that 

 time were but imperfectly understood, aud have suffered much by lbs 

 scour of Uie current ; it will probably be rebuilt iu a short time. Caissons, 

 or water Ugbt dUests, w«r<j 6r« )iitfua«ce(} Uiere for the purpose of fo.uml- 



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