VOL. 4.]

M. Dupin's Journey in England.

471

M. DUPIN'S JOURNEY IN ENGLAND.
From the New Monthly Magazine, December 1818.

BRIEF ACCOUNT OF THE FIRST JOURNEY IN
England, in 1816, mADE BY M. CHARLES

DUPIN.*

M. Dupin observes, that the favour with which his former labours have been honoured, in which it seems he has de

N a modest address to the French scribed whatever is worthy of notice re

a

*M. DUPIN is a protege of the celebrated Carnot, and a brother of the advocate M. DuPIN, who defended Sir ROBERT WILSON in his trial. He was educated at the Polytechnic School, and was a favorite pupil of M. MONGE, the founder of that School. Recently, on the death of his illustrious preceptor, he has been appointed to fill his place as a member of the Institute. M. Dupin is a Captain of Engineers, and a superintendant of the marine constructions in the Dock-yard at Dunkirk, He is about 30 years of age, and, being equal ly conversant with the mathematical and physical sciences, and with several of their practical applications, while he possesses an ardent and enterprising spirit: it seems to have occur red to him that he could not find a readier road to distinction, than would present itself in a careful scientific examination of the principal military, maritime, and commercial establish ments of Great Britian.

We think it due to M. Dupin to say, that he has conducted his enquiries, and detailed his

ments, has stimulated him to examine the same sort of establishments amongst a people who, for more than a century, have held the sceptre of the seas, and who, instead of resting satisfied with the superiority they have attained, endeavour most sedulously to approach towards perfection.

The author then proceeds to speak in the highest terms of the kindness and polite assistance he received in England from the most illustrious men of science, who were eager to testify their friendship for him, and to evince their respect for those members of the Institute who had furnished him with letters of recommendation. "The names of Berthol

the establishments of London, which In my first tour (says he)* I visited are connected either directly or indirectly with the Navy, all the grand military stations, and the two most important commercial ports, next to the capital, those of Bristol and Liverpool.

results, with a mind far more free from nation- let, Humboldt, Lacepede, Prony, &c. al prejudices, than any preceding scientific (says he) opened to me the cabinet of traveller from the same country.--- His feelings the philosopher, as well as the workas a Frenchman, however, lead him to one mistaken inference, which, as it pervades the rooms of the artists; so that by time and whole volume from which this narrative is ex- perseverance I gained the object of my tracted, we shall briefly correct. M. Dupin aim." He then proceeds to give the regards most of the great works, which he saw in the British empire, as resulting from the following outline of his visits and obserimpulse given to the arts and sciences by the vations, which is however, to be enFrench Revolution; and especially as practi- larged upon so as to form an elaborate cal applications of the profound theories developed within the last 30 years, by the memwork. bers of the French Institute. With no wish whatever to depreciate the inventions and discoveries of that learned body, we can most seriously and conscientiously assure M. Dupin, that all he saw and admired in England, would have been precisely the same if those ingenious mathematicians and philosophers had never written a single line. The architects and civil engineers of Britain, are none of them profound mathematicians. Scarcely any of them know more than the rudiments of mechanics, hydrodynamics, and pneumatics, but happily, these are sufficient to preserve them from errors in their constructions. Even the Descriptive Geometry, so peculiarly fitted, as the French conceive, to guide the labours of architects and engineers, and to the perfection of which MONGE, HACHETTE, and our author, M. DUPIN, have so richly contributed, is scarcely known, except to our theoretical mathematicians; our practical men are, with a few exceptions, as ignorant of this elegant product of French ingenuity, as they are of La Place's elaborate investigations in physical astronomy. No; our architects and engineers derive their eminence as their great works do

London offered itself to my observation under three different points of view: First, as the greatest mercantile port of the kingdom; secondly, as a focus

their value, from other sources than those to which M. Dupin usually adverts; and we are persuaded that if a man of his acumen should honour this country with a third visit, he will be able to trace them to those sources.

* The author made two visits to England for the purposes in question, one in 1816 and the other in the last and present year.

472

M. Dupin's Journey in England.

of industry for whatever relates to the maritime arts; and thirdly, as the centre of the operations of the British Navy. Let us then take a rapid survey of the capital of that Empire, under these different aspects.

London enjoys naturally an advantage which Paris ought to have enjoyed long since, through the efforts of art, that of being a maritime port. Large ships go up the Thames in full sail, and come to anchor almost at the arches of London Bridge. On going down the river towards the sea, you see on each side of it, five, six, seven, or eight vessels ranged alongside each other, and these lines succeed almost without interruption, to an immense length. Nevertheless, this is only a portion of the merchant ships of the capital. All those which belong to the EAST INDIA TRADE have their Ďocks and private Basons, one for import and another for export-goods. All the ships which carry on the WEST INDIA TRADE have their's also; and the ships of all nations are indiscriminately received in the LONDON DOCKS, while the GREENLAND DOCK, formerly appropriated to the vessels concerned in the whale fishery, being enlarged by the labours of late years, is now devoted to a more extensive object.

It is not more than twenty years since this last mentioned Dock, now the smallest of all, was the only one in that quarter. The war breaking out, and the Continent of Europe becoming impoverished, the commerce of England seemed to withdraw before our victorious flags, and we thought that Great Britain was exhausted, and on the point of ruin. But while our eyes were beclouded by the incense from the altars of our glory, an unlooked-for opulence overflowed the British Empire; her rivers were no longer large enough to hold all the ships, and a lesser number of years sufficed for private individuals to construct, at their own expense, the Docks which receive the merchant fleets of the two hemispheres, than was required for a triumphant Government to build a few of the quays on the Seine. Such are the prodigies of the ocean!

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This great lesson will perhaps enable us at a future time to understand the real sources of power and national prosperity. But I must bere confine myself to speaking of the chef-d'œuvres of art, and not of their results.

The formation and building of the Wet Docks and Basons of England differ essentially from labours of the same kind which have been executed in France.-Instead of being, like ours, bounded by quays, formed of smooth walls, inclined or vertical, with stones placed in horizontal layers, these walls are concave at the exterior, or the side next the water; and the layers of stone are joined perpendicularly at the surface. The piles are also inclined, and planted perpendicularly to the inferior face of the lowest stratum. The entry to the sluices is built upon a similar and equally advantageous plan. In short, the flood-gates, instead of being formed by two masses, plain and abutting at the ends are formed by two vertical cylin ders, the convexity of which makes an arch or vault, for resisting the pressure of the water. The advantage of these curvilinear over our rectilinear forms, with respect to economy and solidity, can be geometrically demonstrated.

Hydraulic works in England are distinguished by the constant use of the steam-engine for exhaustion, and for all those manœuvres which require great and continual efforts on the spot. The removal of earth, the conveyance of stones, sand, lime, &c. are all performed by little four-wheeled carriages, drawa by one horse, and moving on an iroa rail-way. These roads are composed of materials that are laid down and removed with the greatest facility, and the advantage they afford is immense. Indeed England is indebted to them for a part of her riches; for without them coals, minerals, and primary substances of all kinds, could never have been conveyed to great distances at hardly any expense.

The excavations under water, when the bottom is muddy or sandy, are made by a chaplet or line of buckets, fixed on the sides of barges, and kept in circular motion by a steam-engine. I shall speci fy as a model of this mode of clearing,

VOL. 4.]

Dupin's Journey in England-Diving Bells.

the machine employed at the West India Docks.

473

On enter

ed over any desired point. ing it they descend at pleasure by the aid of the axle, and the chain or rope. This apparatus is employed in building those parts of the walls of a quay which lie under water, and thus it is unnecessary to have recourse to the expensive method of erecting coffer-dams. Sometimes the bell is suspended at the of a vessel which conveys it where repoop quired. This machine is also employed to raise in rivers, road-steads, harbours, and docks, any ponderous articles which may have sunk, such as anchors cannon, the remains of wrecked ships, &c. It is likewise made use of to prepare, for being blown up, rocks which are under water, and dangerous to nav

A barge bearing the steam-engine which moves the buckets, is conveyed to any part of the Docks, the bottom of which it is necessary to clear or cleanse. Another vessel of the barge kind, which is to receive and carry away the excavated mud or sand, is fixed alongside the former, and receives the contents of the buckets as they empty themselves by their rotatory motion. When a barge is loaded it moves off, and another takes its place; it is then laid under another line of buckets, moved by another engine, stationed at the edge of the Dock. The contents are thus raised and emptied into vehicles which go round the wall of the build-_igation.* ing, and spread thein like a torrent, in a large vacant spot. This system of clearing is not only extremely simple, but vastly economical. By means of the apparatus here described, the English have not only dug out and cleared large basons, but have rendered streams navigable which were not so before, and have also removed sand-banks which obstructed certain parts of the course of their most impor

tant rivers.

Another machine not less remarkable, and which is employed in all grand hydraulic works, is the Diving-bell. The form of the kind now in general use, is that of a truncated square pyramid, the great base of which is open and turned towards the bottom. Within this pyramidal trunk, two men, who descend sitting on two benches, can rise and work at their ease. Ten lenticular glasses fixed in the upper base of the bell, combine to refract, as much light as gives the requisite illumination at a great depth under water. A paeumatic machine resembling a fire-engine, serves by means of a long leather tube, to convey fresh air incessantly into the bell.

Sometimes this bell is suspended to a moveable axle, formed of two systems of indented bars, which, by their directions and functions, represent co-ordinate rectangular axles. By means of these axles the centre of the hell is plac

3 M

ATHENEUM VOL. 4.

Hence, if we consider the machinery now employed by the English in their great undertakings, we shall find that an immense change has been effected in the course of a few years.

The basons and other works built in former times were enclosed by a simple system of timber-work. It was however thought, and with reason, that by devoting a small capital to these la bours, the expense of keeping in repair and renewing such perishable constructions would be repaid with interest. But when maritime operations assumed an excessive activity, it was perceived that their frequent interruption, produced by repairs and rebuilding, caused a loss which might be amply repaid by a moderate expenditure. Upon this principle, bricks and castiron have been gradually subsituted for wood in the docks of commerce; and

to which we have pointed in a preceding anno* We know not whether it be the prejudice tation, or real ignorance of any such apparatus, bell among the inventions of the last 30 that should lead M. Dupin to class the Divingyears. He might have learnt from any of our Encyclopædias, and from some such works ployed in raising some of the treasure lost in printed at Paris, that Diving-bells were emthe ships of the Spanish Armada, that were sunk near the isle of Mull in 1588: that Sintis, 1669), Phipps, Kessler, Halley, Triesclair (ars nova et magna gravitatis et levitawald, Spalding, Smeaton, and a long list of 30, but of 230 years, brought the apparatus others in succession, had in the compass, not of from the rude state in which it first existed, to cle which he describes. the finished, elegant, and safe submarine vehi

474

Dupin's Journey in England-Iron Storehouses.

free-stone, marble, and granite, in the ports of the state.

This change is very striking along the banks of the Thames, where the oldest dock-yards still contain basons and slips constructed of wood; while the more modern establishments present nothing but quays and embankments of masonry. Along the Thames there are but very few of those modes of building formed by imbedding the hull of an old vessel in the soil of the shore, with its end next the river cut open for a flood-gate. Another change not less remarkable is effected in the timber edifices built on land. Whereever there was reason to fear accidents from fire, wood has been replaced by iron.

One of the finest works of this kind is a storehouse built by Mr. Rennie, along the grand West India Dock. It is eight hundred yards long, and is sustained by hollow columns of iron; the beams, the joists, the rafters and laths are likewise all of iron. Those parts which have only pressure to bear are of cast-iron; those which have to resist tension are of wrought-iron. The longitudinal elements of this system are so combined, that its various parts can either be extended or contracted, with out altering the whole length of the building. If this precaution had not been taken, it is apprehended that the least variation of temperature, would upon a length of eight hundred yards, have thrown out the extreme columns, and quickly have effected the destruction of the whole edifice.

In the course of this memoir I shall have several opportunities of mentioning the new and ingenious purposes to which wrought and cast-iron are applied in England.

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the Thames. I saw one of the India company's ships launched from it, of 1300 tons burthen. This ship was a model of perfection; there were three others of a similar size, on slips in the same yard.

London, considered as a focus of industry for the maritime arts, contains a number of important establishments.--The Royal Society of London, the Society for the encouragement of Arts, the British Museum, and the Royal Institution, are the principal sources from which to collect materials for the theoretical part. It is about thirty years since a society was formed for the improvement of naval architecture; it made many very important experiments in Greenland Dock, on the resistance experienced by bodies moving in water. This society, abandoned by the Government, and perhaps counteracted secretly by powerful individuals, was dissolved after ten years of commendable labours.

With respect to the practical part of the maritime arts, I shall mention some of the principal establishments that I visited.

The manufactory of MAUDSLEY, in the Borough of Southwark, is one of the most interesting in reference to applications of iron. There may be seen in the Conservatory of the Arts and Trades at Paris, one of the small steam-engines made at this manufactory. At the same place were made the machines of M. BRUNEL, of which I shall presently have occasion to speak. There were also made at it, for the British Navy, 7000 iron cases, each capable of containing about two cubic metres of water. The introduction of these water-boxes on board ships is an incalculable advantage, both for preserv ing the purity of the water and the health of the crews.

In another part of London, Messrs. HUDDART and BROWN have established two manufactories, one for ships' cordage, and the other for iron cables.

The great docks or basons of London are surrounded by cellars, storehouses, and sheds of an immense extent. The quays are often covered with iron rail-ways, and have numerous cranes likewise of iron, which are' of various sizes, shapes, and me----HUDDART's ropes are spun and formchanism. ed by the action of steam, on the principle of equal tension of all the threads, which gives them much greater strength

Near to the East India Docks is the largest commercial Dock-yard along

Morier's Travels—Water turned into Marble.

WATER TURNED INTO MARBLE....MOUNT ARARAT. From the Literary Gazette.

▲ SECOND JOURNEY THROUGH PERSIA, AR- in most of the burial places in Persia,