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experiment on a circle of such an extensive diameter had ever been made in architecture, or the practicability of it supposed.

The rib was erected between a wall of a furnace belonging to the iron works, and the gable end of a brick building, which serv ed as butments. The weight of iron in the rib, was three tons, and we loaded it with double its weight in pig iron. I wrote to Mr. Jefferson, who was then at Paris, an account of this experiment; and also Sir Joseph Banks in London, who in his answer to me says "I look for many other bold improvements from your countrymen, the Americans, who think with vigor, and are not fettered with the trammels of science before they are capable of exerting their mental faculties to advantage." On the success of this experiment, I entered into an agreement with the ironfounders at Rotherham to cast and manufacture a complete bridge, to be composed of five ribs of 210 feet span, and 5 feet of height from the cord line, being a segment of a circle 610 feet diameter, and send it to London, to be erected as a specimen for establishing a manufactory of iron bridges, to be sent to any part of the world.

The bridge was erected at the village of Paddington, near London, but being in a plain field, where no advantage could be taken of butments without the expense of building them, as in the former case, it served only as a specimen of the practicability of a manufactory of iron bridges. It was brought by sea, packed in the hold of a vessel, from the place where it was made; and after standing a year was taken down, without injury to any of its parts, and might be erected any where else.

At this time my bridge operations became suspended. Mr. Edmund Burke published his attack on the French revolution and the system of representative government, and in defence of government by hereditary succession, a thing which is in its nature an absurdity, because it is impossible to make wisdom hereditary; and therefore, so far as wisdom is necessary in a government, it must be looked for where it can be found. Sometimes in one family; sometimes in another. History informs us that the son of Solomon was a fool. He lost ten tribes out of twelve.* There are those in later times who lost thirteen.

The publication of this work by Mr. Burke, absurd in its principles and outrageous in its manner, drew me, as I have said, from

* 2 Chron. chap. 10.

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my bridge operations, and my time became employed in defending a system then established and operating in America, and which I wished to see peaceably adopted in Europe-I therefore ceased my work on the bridge to employ myself on the more necessary work, Rights of Man, in answer to Mr. Burke.

In 1792, a convention was elected in France for the express purpose of forming a constitution on the authority of the people, as had been done in America, of which convention I was elected a member. I was at this time in England, and knew nothing of my being elected till the arrival of the person who was sent officially to inform me of it.

During my residence in France, which was from 1792 to 1802, an iron bridge of 236 feet span, and 34 of height from the cord line, was erected over the river near Wear at the town of Sunderland, in the county of Durham in England. It was done chiefly at the expense of the two members of parliament for that county, Milbanke and Burdon.

It happened that a very intimate friend of mine, Sir Robert Smith (who was also an acquaintance of Mr. Monroe, the American minister, and since of Mr. Livingston) was then at Paris. He had been a colleague in parliament, with Milbanke, and supposing that the persons who constructed the iron bridge at Sunderland, had made free with my model, which was at the iron works where the Sunderland bridge was cast, he wrote to Milbanke on the subject, and the following is that gentleman's answer. "With respect to the iron bridge over the river Wear at Sunderland, it certainly is a work well deserving admiration, both for its structure and utility, and I have good grounds for saying that the first idea was suggested by Mr. Paine's bridge exhibited at Paddington. What difference there may be in some part of the structure, or in the proportion of wrought and cast iron, I cannot pretend to say, Burdon having undertaken to build the bridge, in consequence of his having taken upon himself whatever the expense might be beyond between three and four thousand pounds sterling, subscribed by myself and some other gentlemen. But whatever the mechanism might be, it did not supersede the necessity of a centre.* (The writer has here confounded a centre

It is the technical term, meaning the boards and numbers which form the arch upon which the permanent materials are laid; when a bridge is finished the workmen say they are ready to strike centre, that is to take down the scaffolding.

with a scaffolding) which centre (continues the writer) was esteemed a very ingenious piece of workmanship, and taken from a plan sketched out by Mr. Nash, an architect of great merit, who had been consulted in the outset of the business, when a bridge of stone was in contemplation.

"With respect therefore to any gratuity to Mr. Paine, though ever so desirous of rewarding the labors of an ingenious man, I do not feel, how, under the circumstances already described, I have it in my power, having had nothing to do with the bridge after he payment of my subscription, Mr. Burdon then becoming accountable for the whole. But if you can point out any mode, according to which it would be in my power to be instrumental in procuring him any compensation for the advantages the public may have derived from his ingenious model, from which certainly the outline of the bridge at Sunderland was taken, be assured it will afford me very great satisfaction.*

RA. MILBANKE.”

The year before I left France, the government of that country had it in contemplation to erect an iron bridge over the river Seine, at Paris. As all edifices of public construction came under the cognizance of the minister of the interior,-(and as their plan was to erect a bridge of five iron arches of one hundred feet span each, instead of passing the river with a single arch, and which was going backward in practice, instead of forward, as there was already an iron arch of 230 feet in existence) I wrote the minister of the interior, the citizen Chaptal, a memoir on the construction of iron bridges. The following is his answer.

The minister of the interior to the citizen Thomas Paine.

I have received, citizen, the observations that you have been so good as to address to me upon the construction of iron bridges. They will be of the greatest utility to us, when the new kind of construction goes to be executed for the first time. With pleasure, I assure you, citizen, that you have rights of more than one kind to the thankfulness of nations, and I give you, cordially, the particular expression of my esteem.†

* The original is in my possession.

†The original, in French, is in my possession.

W

CHAPTAL.

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A short time before I left France, a person came to me from London with plans and drawings for an iron bridge of one arch over the river Thames at London, of 60, feet span, and sixty feet of height from the cord line. The subject was then before a committee of the house of commons, but I know not the proceedings thereon.

As this new construction of an arch for bridges, and the principles on which it is founded, originated in America, as the documents I have produced sufficiently prove, and is becoming an object of importance to the world, and to no part of it more than to our own country, on account of its numerous rivers, and as no experiment has been made in America to bring it into practice, further than on the model I have executed myself, and at my own expense, I beg leave to submit a proposal to congress on the subject, which is,

To erect an experiment rib of about 400 feet span, to be the segment of a circle of at least 1000 feet diameter, and to let it remain exposed to public view, that the method of constructing such arches may be generally known.

It is an advantage peculiar to the construction of iron bridges, that the success of an arch of a given extent and height, can be ascertained without being at the expense of building the bridge; which is, by the method I propose, that of erecting an experiment rib on the ground where advantage can be taken of two hills for butments.

manner.

I began in this manner with the rib of 90 feet span, and 5 feet of height, being a segment of a circle of 410 feet diameter. The undertakers of the Sunderland bridge began in the same They contracted with the iron-founder for a single rib, and finding it to answer, had five more manufactured like it, and erected into a bridge consisting of six ribs, the experiment rib being one. But the Sunderland bridge does not carry the principle much further into practice than had been done by the rib of 90 feet span and 5 feet in height, being, as before said, a segment of a circle of 410 feet diameter; the Sunderland bridge being 206 feet span and 34 feet of height, gives the diameter of the circle of which it is a segment, to be 444 feet, within a few inches, which is but a larger segment of a circle of 30 feet more diameter.

The construction of those bridges does not come within the line of any established practice of business. The stone architect

can derive but little from the theory or practice of his art that enters into the construction of an iron bridge; and the ironfounder, though he may be expert in moulding and casting the parts, when the models are given him, would be at a loss to proportion them, unless he was acquainted with all the lines and properties belonging to a circle.

If it should appear to congress that the construction of iron bridges will be of utility to the country, and they should direct hat an experiment rib be made for that purpose, I will furnish the proportions for the several parts of the work, and give my attendance to superintend the erection of it.

But, in any case, I have to request, that this memoir may be put on the journals of congress, as an evidence hereafter, that this new method of constructing bridges originated in America. THOMAS PAINE.

Federal city, Jan. 3, 1803.

N. B. The two models mentioned in the memoir, will, I ex pect, arrive at Philadelphia, by the next packet, from the federal city, and will remain for some time in Mr. Peale's museum.

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USEFUL AND ENTERTAINING HINTS.*

"The real value of a thing,

Is as much money as 'twill bring."

IN the possession of the Philadelphia Library Company is a cabinet of fossils,† with several specimens of earth, clay, sand, &c. with some account of each, and where brought from.

I have always considered these kind of researches as productive of many advantages, and in a new country they are particularly so. As subjects for speculation, they afford entertainment

* Published in the Pennsylvania magazine, Feb. 1775.

† In the catalogue it is called a collection of American fossils, &c. but a considerable part of them are foreign ones. I presume that the collector, in order to judge the better of such as he might discover here, made first a collection of such foreign ones whose value were known, in order to compare by: as his design seems rather bent towards discovering the treasures of America than merely to make a collection.

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