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PLANS OFFERED FOR THE
CONSTRUCTION OF BLACK-FRIARS BRIDGE.
IN THREE LETTERS, TO THE PRINTER OF THE GAZETTEER.
left by a wedge driven between them. In pro
portion as the stones are wider at the top than Dec. 1st, 1759.
at the bottom, they can less easily be forced Sir,
downwards, and as their lateral surfaces tend The Plans which have been offered by different more from the centre to each side, to so much architects, of different reputation and abilities, more is the pressure directed laterally towards for the construction of the Bridge intended to the piers, and so much less perpendicularly tobe built at Black-Friars, are, by the rejection wards the vacuity. of the greater part, now reduced to a small
Upon this plain principle the semicircular number; in which small number, three are sup- arch may be demonstrated to excel in strength posed to be much superior to the rest ; so that the elliptical arch, which approaching nearer only three architects are now properly compe- to a straight line, must be constructed with titors for the honour of this great employment; stones whose diminution downwards is very by two of whom are proposed semicircular, and by little, and of which the pressure is almost perthe other elliptical arches.
pendicular. The question is, therefore, whether an ellipti- It has yet been sometimes asserted by hardy cal or semicircular arch is to be preferred ? ignorance, that the elliptical arch is stronger than
The first excellence of a bridge built for com- the semicircular; or in other terms, that any merce over a large river, is strength; for a mass is more strongly supported the less it rests bridge which cannot stand, however beautiful, upon the supporters. If the elliptical arch be will boast its beauty but a little while; the equally strong with the semicircular, that is, stronger arch is therefore to be preferred, and if an arch, by approaching to a straight line, much more to be preferred, if with greater loses none of its stability, it will follow, that all strength it has greater beauty.
arcuation is useless, and that the bridge may at Those who are acquainted with the mathe- last without any inconvenience, consist of stone matical principles of architecture, are not many; laid in straight lines from pillar to pillar. But and yet fewer are they who will, upon any sin- if a straight line will bear no weight, which is gle occasion, endure any laborious stretch of evident at the first view, it is plain likewise, that thought, or harass their minds with unaccus- an ellipsis will bear very little ; and that as the tomed investigations. We shall therefore at- arch is more curved, its strength is increased. tempt to show the weakness of the elliptical arch, Having thus evinced the superior strength by arguments which appear simply to common of the semicircular arch, we have sufficiently reason, and which will yet stand the test of geo-proved, that it ought to be preferred ; but to metrical examination.
leave no objection unprevented, we think it All arches have a certain degree of weak- proper likewise to observe, that the elliptical
No hollow building can be equally strong arch must always appear to want elevation and with a solid mass, of which every upper part dignity; and that if beauty be to be deterpresses perpendicularly upon the lower. Any mined by suffrages, the elliptical arch wil weight laid upon the top of an arch, has a ten- have little to boast, since the only bridge of tha dency to force that top into the vacuity below; kind has now stood two hundred years without and the arch thus loaded on the top, stands only imitation. because the stones that form it, being wider in If in opposition to these arguments, and in the upper than in the lower parts, that part defiance at once of right reason and general that fills a wider space cannot fall through a authority, the elliptical arch should at last be space less wide; but the force which laid upon chosen, what will the world believe, than that a flat would press directly downwards, is dis- some other motive than reason influenced the persed each way in a lateral direction, as the determination ? And some degree of partiality parts of a beam are pushed out to the right and cannot but be suspected by him, who has been
old that one of the judges appointed to decide pears to me unworthy of debate. I suppose this question, is Mr. M_—, who having by every judicious eye will discern it to be minute ignorance, or thoughtlessness, already preferred and trifling, equally unfit to make a part of a the elliptical arch, will probably think himself great design, whatever be its colour. I shall obliged to maintain his own judgment, though only observe how little the writer understands his opinion will avail but little with the public, bis own positions, when he recommends it to be when it is known that Mr. S—ps-n declares it cast in whole pieces from pier to pier. That to be false.
iron forged is stronger than iron cast, every He that in the list of the committee chosen smith can inform him ; and if be cast in large for the superintendency of the bridge, reads pieces, the fracture of a single bar must be remany of the most illustrious names of this great paired by a new piece. city, will hope that the greater number will The abrupt rise which is feared from firm have more reverence for the opinion of poste- circular arches, may be easily prevented, by a rity, than to disgrace themselves, and the me- little extension of the abutment at each end, tropolis of the kingdom, in compliance with any which will take away the objection, and add alman, who, instead of voting, aspires to dictate, most nothing to the expense. perhaps without any claim to such superiority, The whole of the argument in favour of Mr. either by greatness of birth, dignity of employ- M-, is only that there is an elliptical bridge ment, extent of knowledge, or largeness of at Florence, and an iron balustrade at Rome; fortune.
the bridge is owned to be weak, and the iron balustrade we consider as mean; and are loth that our own country should unite two follies
in a public work. LETTER II.
The architrave of Perault, wbich has been
pompously produced, bears nothing but its en
Dec. 8th, 1759. tablature; and is so far from owing its support Sir,
to the artful section of the stone, that it is held In questions of general concern, there is no law together by cramps of iron; to which I am of government or rule of decency, that forbids afraid Mr. M_must have recourse, if be open examination and public discussion. I persists in his ellipsis, or, to use the words of shall therefore not betray, by a mean apology, his vindicator, forms his arch of four segments that right which no man has power, and, I sup- of circles drawn from four different centres. pose, no wise man has desired to refuse me; but That Mr. M obtained the prize of the shall consider the Letter published by you last architecture at Rome, a few months ago, is willFriday, in defence of Mr. M—'s* design for a ingly confessed ; nor do his opponents doubt new bridge.
that he obtained it by deserving it. May he Mr. M-proposes elliptical arches. It continue to obtain whatever he deserves ; bus has been objected that elliptical arches are let it not be presumed that a prize granted at weak: and therefore improper for a bridge of Rome, implies an irresistible degree of skill. commerce, in a country where greater weights The competition is only between boys, and the are ordinarily carried by land than perhaps in prize given to excite laudable industry, not to any other part of the world. That there is an reward consummate excellence. Nor will the elliptical bridge at Florence is allowed, but the suffrage of the Romans much advance any name objectors maintain, that its stability is so much among those who know, what no man of science doubted, that carts are not permitted to pass will deny, that architecture has for some time over it.
degenerated at Rome to the lowest state, and To this no answer is made, but that it was that the Pantheon is now deformed by petty built for coaches; and if it had been built for decorations. I am, Sir, yours, &c. carts, it would have been made stronger : thus all the controvertists agree, that the bridge is too weak for carts; and it is of little importance, whether carts are prohibited because the bridge
LETTER 111. is weak, or whether the architect, knowing that carts were prohibited, voluntarily constructed a
Dec. 15th, 1759. weak bridge. The instability of the elliptical Sir, arch has been sufficiently proved by argument, It is the common fate of erroneous positions, and Ammanuti's attempt has proved it by ex- that they are betrayed by defence, and obscured ample.
by explanation ; that their authors deviate from The iron rail, whether gilt or varnished, ap. the main question into incidental disquisitions,
and raise a mist where they should let in light.
Of all these concomitants of errors, the Letter * Mr. Mylue.
of Dec. 10th, in favour of elliptical arches, has
afforded examples. A great part of it is spent be thus at variance with himself, little doubt can upon digressions. The writer allows, that the be made of his contrariety to others; nor do I first excellence of a bridge is undoubtedly strength : think myself entitled to complain of disregard but this concession affords him an opportunity from one, with whom the perforinances of anof telling us, that strength, or provision against tiquity have so little weight : yet in defiance of decay, has its limits; and of mentioning the all this contemptuous superiority, I must again Monument and Cupola, without any advance venture to declare, that a straight line will bear towards evidence or argument.
no weight; being convinced, that not even the The first excellence of a bridge is now allowed science of Vasari can make that form strong to be strength; and it has been asserted, that a which the laws of nature have condemned to semi-ellipsis has less strength than a semicircle. weakness. By the position, that a straight line To this be first answers, that granting this posi- will bear nothing, is meant, that it receives no tion for a moment, the semi-ellipsis may yet strength from straightness ; for that many bodies, have strength sufficient for the purposes of com. laid in straight lines, will support weight by the
This grant, which was made but for a cohesion of their parts, every one has found, moment, needed not to have been made at all; who has seen dishes on a shelf, or a thief upon for before he concludes his Letter, he under- the gallows. It is not denied, that stones may takes to prove, that the elliptical arch must in be so crushed together by enormous pressure on all respects be superior in strength to the semi- each side, that a heavy mass may safely be laid circle. For this daring assertion he made way upon them; but the strength must be derived by the intermediate paragraphs; in which he merely from the lateral resistance; and the line observes, that the convexity of a semi-ellipsis so loaded will be itself part of the load. may be increased at will to any degree that The semi-elliptical arch has one recommendastrength may require: which is, that an elliptical tion yet unexamined; we are told that it is difarch may be made less elliptical, to be made ficult of execution. Why difficulty should be less weak; or that an arch, which by its ellip-chosen for its own sake, I am not able to distical form is superior in strength to the semi- cover; but it must not be forgotten, that as the circle, may become almost as strong as a semi-convexity is increased, the dificulty is lessened ; circle, by being made almost semicircular. and I know not well whether this writer, whe
That the longer diameter of an ellipsis may appears equally ambitious of difficulty and stube shortened, till it shall differ little from a cir- dious of strength, will wish to increase the concle, is indisputably true; but why should the vexity for the gain of strength, or to lessen it for writer forget the semicircle differs as little from the love of difficulty. such an ellipsis? It seems that the difference, The friend of Mr. M- however he may whether small or great, is to the advantage of be mistaken in some of his opinions, does not the semicircle ; for he does not promise that the want the appearance of reason, when he prefers elliptical arch, with all the convexity that his facts to theories; and that I may not dismiss imagination can confer, will stand without the question without some appeal to facts, I will cramps of iron, and melted lead, and large stones, borrow an example, suggested by a great artist, and a very thick arch; assistances which the and recommended to those who may still doubt semicircle does not require, and which can be which of the two arches is the stronger, to press yet less required by a semi-ellipsis, which is in an egg first on the ends, and then upon the all respects superior in strength.
sides. I am, Sir, yours, &c. vi a man who loves opposition so well, as to
SOME THOUGHTS ON AGRICULTURE,
BOTH ANCIENT AND MODERN;
WITH AN ACCOUNT OF THE HONOUR DUE TO AN ENGLISH FARMER.
FROM THE UNIVERSAL VISITOR FOR FEB. 1756.
AGRICULTURE, in the primeval ages, was the mankind then consisted in cattle, and the procommon parent of traffic : for the opulence of duct of tillage; which are now very essential
for the promotion of trade in general, but more ported the metropolis of tho world; which, particularly so to such nations as are most abun- without this supply, would have been in danger dant in cattle, corn, and fruits. The labour of of perishing by famine. Rome actually saw the farmer gives employment to the manufac- herself reduced to this condition under Auturer, and yields a support for the other parts gustus; for there remained only three days' of the community: it is now the spring which provision of corn in the city; and that prince sets the whole grand machine of commerce in was so full of tenderness for the people, that motion; and the sail could not be spread with he bad resolved to poison himself, if the exout the assistance of the plough. But though pected fleets did not arrive before the expirathe farmers are of such utility in a state, we tion of that time; but they came; and the prefind them in general too much disregarded servation of the Romans was attributed to the among the politer kind of people in the present good fortune of their emperor; but wise preage ; while we cannot help observing the hon- cautions were taken to avoid the like danger for our that antiquity has always paid to the pro- the future. fession of the husbandman; which naturally When the seat of empire was transplanted to leads us into some reflections upon that occa- Constantinople, that city was supplied in the sion.
same manner; and when the emperor Septimius Though mines of gold and silver should be Severus died, there was corn in the public maexhausted, and the species made of them lost; gazines for seven years, expending daily 75,000 though diamonds and pearls should remain con- bushels in bread, for 600,000 men. cealed in the bowels of the earth, and the womb The ancients were no less industrious in the of the sea ; though commerce with strangers cultivation of the vine than in that of corn, be prohibited; though all arts which have no though they applied themselves to it later : for other object than splendour and embellishment, Noah planted it by order, and discovered the should be abolished; yet the fertility of the use that might be made of the fruit, by pressing earth alone would afford an abundant supply for out and preserving the juice. The vine was the occasions of an industrious people, by fur- carried by the offspring of Noah into the senishing subsistence for them, and such armics veral countries of the world: but Asia was the as should be mustered in their defence. We, first to experience the sweets of this gift; from therefore, ought not to be surprised, that agri- whence it was imparted to Europe and Africa. culture was in so much honour among the an- Greece and Italy, which were distinguished in cients : for it ought rather to seem wonderful so many other respects, were particularly so by that it should ever cease to be so, and that the the excellency of their wines. Greece was most necessary and most indispensable of all most celebrated for the wines of Cyprus, Lesprofessions should have fallen into any con- bos, and Chio; the former of which is in great tempt.
esteem at present: though the cultivation of Agriculture was in no part of the world in the vine has been generally suppressed in the higher consideration than Egypt, where it was Turkish dominions. As the Romans were inthe particular object of government and policy: debted to the Grecians for the arts and sciences, nor was any country ever better peopled, richer, so were they likewise for the improvement of or more powerful. The Satrapce, among the their wines ; the best of which were produced Assyrians and Persians, were rewarded, if the in the country of Capua, and were called the lands in their governments were well cultivated; Massick, Calenian, Formiau, Cæcuban, and but were punished, if that part of their duty Falernian, so much celebrated by Horace. Dowas neglected. Africa abounded in corn, but mitian passed an edict for destroying all the the most famous countries were Thrace, Sar- vines, and that no more should be plunted dinia, and Sicily.
throughout the greatest part of the west; which Cato, the censor, has justly called Sicily the continued almost two hundred years afterwards, magazine and nursing mother of the Roman when the emperor Probus employed his solpeople, who were supplied from thence with al- diers in planting vines in Europe, in the same most all their corn, both for the use of the city, manner as Hannibal had formerly employed his and the subsistence of her armies : though we troops in planting olive trees in Africa. Some also find in Livy, that the Romans received no of the ancients have endeavoured to prove, that inconsiderable quantities of corn from Sardinia. the cultivation of vines is more beneficial than But, when Rome had made herself mistress of any other kind of husbandry: but, if this was Carthage and Alexandria, Africa and Egypt be- thought so in the time of Columella, it is very came her store-bouses : for those cities sent | different at present; nor were all the ancients such numerous fleets every year, freighted with of his opinion, for several gave the preference corn, to Rome, that Alexandria alone annually to pasture lands. supplied twenty millions of bushels : and, when The breeding of cattle has always been con. the harvest happened to fail in one of these sidered as an important part of agriculture. provinces, the other came in to its aid, and sup- The riches of Abraham, Laban, and Job, con
sisted in their flocks and herds. We also find, countries : but England is the happiest spot in from Latinus in Virgil, and Ulysses in Homer, the universe for all the principal kinds of agrithat the wealth of those princes consisted in culture, and especially its great produce of cattle. It was likewise the same among the Romans, till the introduction of money, which The improvement of our landed estates, is put a value upon commodities, and established the enrichment of the kingdom; for, without a new kind of barter. Varro bas not disdained this, how could we carry on our manufactures, to give an extensive account of all the beasts or prosecute our commerce? We should look that are of any use to the country, either for upon the English farmer as the most useful tillage, breed, carriage, or other conveniences member of society. His arable grounds not of man.
And Cato, the censor, was of opinion, only supply his fellow-subjects with all kinds of that the feeding of cattle was the most certain the best grain, but his industry enables him and speedy method of enriching a country. to export great quantities to other kingdoms,
Luxury, avarice, injustice, violence, and am- which might otherwise starve: particularly bition, take up their ordinary residence in po- Spain and Portugal; for in one year, there pulous cities; while the hard and laborious life have been exported 51,520 quarters of barley, of the husbandmen will not admit of these 219,781 of malt, 1,920 of oatmeal, 1,329 of vices. The honest farmer lives in a wise and rye, and 153,343 of wheat; the bounty on happy state, which inclines him to justice, tem- which amounted to 72,433 pounds.
What a perance, sobriety, sincerity, and every virtue fund of treasure arises from his pasture lands, that can dignify human nature. This gave room which breed such innumerable flocks of sheep, for the poets to feign, that Astræa, the goddess and afford such fine herds of cattle, to feed of justice, had her last residence among hus-Britons, and clothe mankind! He rears flax bandmen, before she quitted the earth. Hesiod and hemp for the making of linen; while his and Virgil have brought the assistance of the plantations of apples and hops supply him with muses in praise of agriculture. Kings, gene- generous kinds of liquors. rals, and philosophers, have not thought it un- The land-tax, when at four shillings in the worthy their birth, rank, and genius, to leave pound, produces 2,000,000 pounds a year.
This precepts to posterity upon the utility of the hus- arises from the labour of the husbandman : it is bandman's profession. Hiero, Attalus, and a great sum: but how greatly is it increased by Archelaus, kings of Syracuse, Pergamus, and the means it furnishes for trade? Without the Cappadocia, have composed books for support- industry of the farmer, the manufacturer could ing and augmenting the fertility of their differ- have no goods to supply the merchant, nor the ent countries. The Carthaginian general Mago merchant find any employment for the mariwrote twenty-eight volumes upon this subject ; ners : trade would be stagnated; riches would and Cato, the censor, followed his example. be of no advantage to the great; and labour of Nor have Plato, Xenophon, and Aristotle, omit- no service to the poor. ted this article, which makes an essential part of their politics. And Cicero, speaking of The Romans, as historians all allow, the writings of Xenophon, says, “ How fully Sought, in extreme distress, the rural plough; and excellently does he, in that book called his lo triumphe ! for the village swain, *Economics,' set out the advantages of hus
Retired to be a nobleman * again. bandry, and a country life !"
When Britain was subject to the Romans, she annually supplied them with great quantities of corn; and the Isle of Anglesea was FURTHER THOUGHTS ON AGRICULTURE then looked upon as the granary for the western provinces ; but the Britons, both under the FROM THE VISITOR FOR MARCH, 1756. Romans and Saxons, were employed like slaves at the plough. On the intermixture of the Army last visit, I took the liberty of mentionDanes and Normans, possessions were better ing a subject, which, I think, is not considered regulated, and the state of vassalage gradually with attention proportionate to its importance. declined, till it was entirely wore off under the Nothing can more fully prove the ingratitude of reigns of Henry VII. and Edward VI., for they mankind, a crime often charged upon them, hurt the old nobility by favouring the commons, and often denied, than the little regard which who grew rich by trade, and purchased estates. the disposers of honorary rewards have paid to
The wines of France, Portugal, and Spain, agriculture ; which is treated as a subject so are now the best ; while Italy can only boast of remote from common life, by all those who do the wine made in Tuscany. The breeding of not immediately hold the plough, or give fodder cattle is now chiefly confined to Denmark and Ireland. The corn of Sicily is still in great esteem, as well as what is produced in the northern