proposed to carry the foundations of the abutments down to the solid rock on both sides of the river, instead of-as had been originally intended-building one of the abutments upon piles, on the side where the rock was at a greater depth. The design, thus remodelled, was considered practicable; but nothing was done at the time for want of funds, the cost being estimated at £54,000. Eventually, the late Mr. Jesse Hartley, of Liverpool, was instructed to carry out the work, which he consented to do "on the condition that no alteration should be made from Mr. Harrison's external design, but that the interior and all practical points should be left entirely to him." He gladly availed himself of the scientific investigations of Mr. Rennie, and with the aid of the practical skill of the late Mr. Trubshaw, as the contractor, the present Grosvenor Bridge was built. About the year 1836-37 Mr. Rennie, in conjunction with Messrs. Chapman and Jessop, laid out a line of railway between Birmingham and Liverpool, to cross the Mersey at Runcorn, with a magnificent viaduct. This was to have been connected with another direct line, by Sir John Rennie, between London and Birmingham, passing by the Valley of the Colne, Aylesbury, Bicester, Banbury, and Warwick, which was asserted by the promoters to be more level, easier of execution, and shorter than the present line. Mr. Rennie also laid out several other railways, including a line to connect the east and west parts of London, the Vale of Clwyd line, the Mons and Manège line, &c. In 1846 he was appointed Engineer-in-chief to the Namur and Liège railway, for which he designed three elegant stone bridges, the largest consisting of five arches of 80 feet span each, for crossing the Meuse, at Val St. Lambert. During this period, and subsequently, at the mechanical_engineering establishment of the Messrs. Rennie, in Holland Street, Blackfriars, important works were constructed, of a novel and difficult character, and at a time when the numerous appliances of tools and other arrangements for facilitating works in iron at present in use were comparatively unknown. In the construction of the two shields for the Thames Tunnel, one of the earliest, if not the first, machine on a large scale for planing iron was used, for the purpose of fitting together the different parts, and this machine is still to be seen in Messrs. Rennie's factory. Under the direction of Messrs. Rennie, the first machinery ever used for making biscuits was constructed for the Government establishments at Weevil, near Gosport. The idea of making biscuits by machinery is due to the late Sir Thomas Grant, and his views were carried into practical effect by Messrs. Rennie and their assistant, Mr. Gideon Scott. The corn and chocolate mills at the Deptford Royal Victualling Yard, as well as the more magnificent establishment called the Royal William Victualling Yard, at Cremil Point, near Plymouth, were also due to the skill of the Messrs. Rennie; the latter being completed about the year 1835. Among other works may be enumerated the armoury at Constantinople, capable of making five hundred muskets a day for the Turkish Government; machinery for the arsenals of France, at Chatellerault, Toulon, and Rochefort; machinery for the Russian Government for producing biscuits and for making blocks at Nicolaieff and at Sebastopol, as also for coining at St. Petersburgh; besides engines for several large vessels of war propelled by the screw, including the Smalé frigate, of 400 horse-power, the celebrated Wladimir,' of 400 horse -power, which was sunk at Sebastopol during the siege, the 'Peterhof' and the 'Alexandrina,' yachts of the late Emperor Nicholas, and other steamers on the Black and Caspian seas; likewise dredgingmachines for Cronstadt, Odessa, and the Danube. Messrs. Rennie also designed the great steam factory at Cronstadt, and one, on a reduced scale, at Astrakhan. Messrs. Rennie constructed many marine engines for her Majesty's navy, such as the Samson,' Bulldog, Vulcan,' Megæra,' Reynard,' 'Cruizer,' 'Oberon,' &c., and for her Majesty's yacht the 'Elfin.' In Ábout the year 1836 Mr. Rennie took much interest in the propulsion of vessels by means of the screw. That propeller in various forms had been proposed and partially tried by Duguet in 1727, Painton in 1768, Littleton in 1794, Shorter in 1802, and also by Napier, Tredgold, and Brown about 1825. 1836 Mr. Francis Pettit Smith (Assoc. Inst. C.E.) fixed a screw propeller in the dead wood of the stern of a small open boat, and worked it by a high-pressure engine, making several successful trials with it on the Thames and to Ramsgate. Mr. Rennie and his brother, who saw it, were satisfied that it must eventually succeed on a large scale. A company was accordingly formed to carry it into effect. The Archimedes,' a wooden vessel of 232 tons, was built expressly for the purpose by Mr. Wimshurst; and Messrs. Rennie designed and constructed the engines, of 80 horse-power, with the machinery and the propeller. Notwithstanding the predictions of its failure by some of the best mechanical engineers of the day, who have since adopted it, the 'Archimedes' succeeded perfectly, and attained a speed of 9 miles an hour. Messrs. Rennie subsequently, in 1840, constructed for the Admiralty an iron vessel, called the Dwarf,' of 210 tons, and fitted it with a pair of engines of 120 horse-power, with the requisite machinery and a screw propeller. This vessel, when completed and tried, attained a speed of 12 miles an hour, being 4 miles an hour in excess of the paddle steamers 1 Vide Minutes of Proceedings Inst. C.E., vol. i. (1839), p. 70. then in use in H.M.'s navy. This was the first vessel propelled by a screw introduced into the British navy, and it produced a complete revolution in the military and commercial navies of the whole world. In 1852 Mr. Rennie also took up the subject of double or twin screw propellers, which had been previously proposed by Captain Carpenter,-a system now much in favour for light draft gunboats and for war purposes generally. Thus the first Mr. Rennie introduced the paddle steamboat into the navy in the year 1819, and his sons introduced the screw propeller into the navy in 1840, twenty-one years afterwards. Having naturally a philosophical turn of mind, Mr. Rennie devoted his spare time to scientific pursuits, in making experiments and communicating the results to various scientific bodies. He was elected a Fellow of the Royal Society in 1822, was for several years one of the Vice-Presidents, and succeeded the late Sir John Lubbock as Treasurer, an office which he retained until the year 1850. In 1825 and 1826 he made a number of experiments on the friction of metals and other substances, the results of which were embodied in three Papers communicated to the Royal Society in 1828, and were published in the Philosophical Transactions.' These investigations still hold a place for accuracy and practical value, and at the time may be said to have been quite new, as they preceded by three years similar experiments made by General Morin, who, assisted by the French Government, pursued the subject further. Mr. Rennie was afterwards appointed one of the Royal Commissioners for investigating the strength of iron. In 1834 he wrote a valuable Paper for the British Association, "On the History, Principles, and Practice of Hydrostatics, Hydraulics, and Hydrodynamics," which, although now rather antiquated, is still considered a standard work. In 1840 he presented to The Institution of Civil Engineers an essay on "The Expansion of Arches,"" and in 1855 a "Description of the Bridge Aqueduct of Roque Favour, on the line of the Canal of Marseilles," as well as a "Description of the Pont du Gard."3 In 1856 he communicated a Paper to the British Association, "On the Quantity of Heat developed by Water when rapidly agitated," also another "On the Resistances of Screw Propellers when revolving in Water at different Velocities." In the following year his Paper "On the Employment of Rubble Béton or Concrete in Works of Engineering and Architecture." was read at the Institution, and was rewarded with a Telford Medal. He had previously written "On 1 Vide Phil. Trans. 1829. p. 143. 2 Vide Minutes of Proceedings Inst. C.E., vol. i. (1840), p. 4. 4 Ibid., vol. xvi., p. 80. London, Metropolitan, and other Bridges," for Cooke's "London Bridges," and was the Author of several articles on dredging, mechanics, waterwheels, &c., in Weale's "Rudimentary Treatises,' and in Weale's new edition of Tredgold. He also brought out a new edition in 1841, of "Buchanan's Millwork and Machinery," with all the latest improvements, to which an extensive supplement was added. He was likewise the Author of many miscellaneous Reports on Civil Engineering subjects. In the year 1865, on his way home from the works in Holland Street, Mr. Rennie met with an accident from which he never recovered. He died on the 30th of March (Good Friday), 1866, in the seventy-fifth year of his age; and was buried, on the 5th of April, in the churchyard of the quiet country church of Holmwood Common, near Dorking, Surrey. He was married, in 1828, to Margaret Anne, daughter of the late Sir John Jackson, Bart., M.P., who survived him, and by whom he left issue two sons and one daughter. Mr. Rennie was elected a Member of The Institution of Civil Engineers on the 4th of May, 1811, and served on the Council in the following year, and up to the period of his accident was a constant attendant at the meetings, taking part in the discussions and evincing great interest in the progress of the Society. He was also a Fellow of the Royal Irish Academy, as well as of the Academies of Turin and Rotterdam. Essentially a man of science, both theoretical and practical, he would probably have attained the highest eminence had his attention been devoted exclusively to purely scientific pursuits. Combining great personal worth, simplicity of manner, and scientific attainments, it was no wonder that he possessed the regard and the esteem of all who knew him, and that, while professional intercourse alone was certain to produce lasting friendships, the advantage of a closer intimacy invariably secured unfeigned pleasure. MR. THOMAS RHODES, H. Mem. R. I. A., was born on the 7th March, 1789, at Apperley Bridge, near Bradford, Yorkshire, and received his education at Calverley school. His father, Mr. James Rhodes, was engaged in superintending the construction of the locks, gates, bridges, and other works on the Leeds and Liverpool Canal, when he met with a serious accident which disabled him for life. The eldest son William, was brought up to his father's business, that of a millwright and carpenter, when employed on the works of the Rochdale Canal. Mr. Thomas Rhodes, the subject of this notice, was apprenticed to his brother William, when under 14 years of age. He had thus an opportunity of acquiring a practical knowledge of, and of taking an active part in, the construction of a variety of works, when the division of labour was not carried to so great an extent as at present. Having naturally a taste for mechanical drawing, he devoted himself in his leisure hours to making and copying drawings, which materially aided him in after-life. He remained with his broher for about eight years, and in 1810 was engaged for a short period on the Glasgow and Paisley Canal. In September, 1811, he proceeded to Corpach, at the western extremity of the Caledonian Canal, to take charge of and superintend the erection of the sea lock-gates, bridges, and machinery, the timber and ironwork of which had just arrived from England; and in the course of the following year the gates were hung in their places, to the satisfaction of Messrs. Jessop and Telford, the chief Engineers. As the timber for the other gates had not arrived, Mr. Rhodes was instructed to proceed to the eastern end of the canal, near Inverness, to erect the gates for the sea lock and the second lock. There being a difficulty in procuring timber suitable for any more wooden gates, plans were made for the use of cast iron; and after various experiments by Mr. Rhodes, the other gates throughout the canal were, with the full approval of Mr. Telford, constructed after the same pattern. The swivel bridges, dredging-vessels, hopper and other barges, were built agreeably to the plans prepared by Mr. Rhodes. During an interval of eight months, by order of Mr. Telford, he went to the Bonar bridge, then in course of erection over the Dornach Frith, and superintended the putting in of the coffer-dams, or caissons, and the erection of the scaffolding and centering for the stone arches and the cast-iron arch of 150 feet span. Having completed these works to the satisfaction of Mr. Telford, Mr. Rhodes left the Highlands and the Caledonian Canal in December, 1822. In the following year he was sent by Mr. Telford to take charge of the erection of the iron and woodwork of the Menai and Conway Suspension Bridges in Wales. In 1826, these bridges being finished, Mr. Rhodes was appointed by Mr. Telford Resident Engineer of the St. Katharine's Docks, London. During the execution of these works, Mr. Rhodes was engaged on the works of the Herne Bay Pier, reported on the Graving Dock near the Commercial Dock, London, made plans, specifications, and estimates for Belfast Harbour, a suspension bridge at Clifton, the Llanelly Railway and Docks, the London and Dover Road, and a new bridge across the Lagan at Belfast. In 1831 he surveyed the River Shannon and its tributaries, for the Commissioners of Public Works, Ireland. In 1833, he made plans, specifications, and estimates for the improvement of the River Ouze, which comprised locks at Naburn and Linton, self-acting |