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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[Dkc- 



rules. To this objection two satisfactory replies may be given. In the 

 first place, architecture differs from other fine arts, such as painting or 

 sculpture, in that it is not an imitative or representative art. The ends of 

 painting and sculpture are the gratification of the taste by the representa- 

 tion of beautiful natural forms. But architecture is restricted by the 

 euoflomic purposes of the materials upon which it works. In one sense it 

 stands alone among the fine arts, and is 'he nubleat of them ; for while the 

 results of other arts have no value excep; their beauty, the results of archi- 

 tecture have a two-fold value— beauty and practical utility. The direct 

 and accurate imitation of nature, which in painting or sculpture is the per- 

 fection of excellence, in architecture is simply impracticable. And there- 

 fore we come to this conclusion, that while other works of art are judged 

 by their beauty alone, the works of architecture are to bejudged not merely 

 by their beauty, but by their fit>ess also. This consideration has been 

 much lost sight of by those who attempt to draw analogies between 

 the laws of architecture and those of painting : the neglect of it led, for 

 instance, to Sir Joshua Reynolds's eulogium of the works of Vanbrugh. 



But there is another strong defence against the charge of utilitarianism ; 

 ■which is, that the restrictions which we would lay upon architecture have 

 been proved experimentally to be neither oppressive nor unnecessary. If 

 it were found practically impossible to coir ply with this restriction with- 

 out making the architecture formal and uns ..vying, a ground of complaint 

 against the strictness of the rule might .-x.st; but, in point of fact, the 

 buildings which have displayed the greatest freedom and variety of form 

 have b.-en those in which the canon of constructive faiihfulness has been 

 most scrupulously obeyed. We observe, moreover, in the works of nature, 

 from which all the principles of beauty must ultimately be derived, that 

 the most graceful forms exhibit a wonderful fitness for the useful purposes 

 to which they are applied. The petals of a flower are not merely beauti- 

 ful ornaments; they serve effectually for the protection of the reproductive 

 organs of the plant. The slight swelling or entasis of the slalk of corn 

 not only renders its form graceful, but adds also to the strength necessary 

 for its preservation. Smeaton, in cuoslructing the Eddystone lighthouse, 

 took for his model th>- trunk of the oak, which increases in breadth towards 

 its base, meeting the ground in curved lines which experience has proved 

 to be the most etfecliial for resisting the violence of storms. Lastly, 

 anatomy teaches us that those forms and proportions of the human frame 

 ■which the sculptor considers most beautiful, are the very same which best 

 enable the several members to perform their respective functions. 



Throughout the whole economy of nature this rule is maintained, of 

 making beauty dependent upon utility. The love of the grotesque, or bizarre 



that is, of forms without purpose-'is seldom exhibited except in art. 



It must, therefore, be regarded as a thoroughly artificial taste — a taste, more- 

 over, unknown in the best periods of art. To revert, therefore, to th^; 

 rules of criticism, it is clear that there are two distinct ways of estimating 

 the merits of a building, — one by the eye alone, the other by the eye and 

 judgment. We will not be so intolerant as to assert that all architecture 

 ■which satisfies the eye alone, and not the judgment also, is to be rejected ; 

 but this may be safely set down, that the beauty of such buildings is of a 

 superficial and inferior character, and therefore undeserving of modern 

 imitations. Th-re are, i- ; ct, many buildings, which, from their magnifi- 

 cent size and gorgeous ornai.ient, produce a dazzling eflfect which gradu- 

 al!' diminishes as the eye becomes familiarized with it. But those glorious 

 piles, which exhibit in every part a logical fitness, derive an inner beauty, 

 a tenfold deeper and purer eloquence, from the gratification of the judg- 

 ment. They do not appeal grossly to the senses, the eye does not weary 

 of them after the first impressions are faded ; for every renewed view 

 serves to discover new meaning, and, therefore, new delight. They satisfy 

 the highest test of works of art— they bear studying. 



Applying these considerations to what is usually considered the most 

 magnificent edifice in London, St. Paul's Cathedral. Can the eye fail to 

 be impressed with the depth of shadow, the proportion and variety of the 

 lines, the graceful contour of the dome, and the apparent boldness and skill 

 by which it has been raised at a vast height above the rest of the stru cture ? 

 But how does the admiration lessen when the judgiuent conies into exer- 

 cise; when we find that this boldness in the construction of the dome ex- 

 ists in appearance only ? This dome is not the thing it looks to be, — it is 

 a mere juggle, an ingenious delusion of the sight. It loolis a. mafsive, 

 ponilerous structure, and an integral portion of the building ; it is, ie fact, 

 a mere frame-work of wood, stuck upon the building, and not belonging 

 to it. It appears to rest firmly upon its base ; but, in reality, derives its 

 support from hidden props and chains, and other delusive cootrivances. 



The architect has shown vast ingenuity ; but he has, in this instance, mis- 

 taken his vocation, and invaded the province of the theatrical machinist. 

 A dome should be vaulted, resting nowhere but upon its abutments ; but 

 this sham dome is not vaulted ; il is supported at every part of its concave 

 surface. Had it been made of pasteboard, or canvas stretched on a frame, 

 and painted, it would have looked just as well. 



And the upper half of the side walls of the Cathedral are delusions 

 also. They serve only to conceal the fljing buttresses behind them. They 

 do not add to the internal capacity of the building; and if they were re- 

 moved altogether, the alteration would not be visible from llie interior. 

 On the outer or conspicuous side, little columns are affixed midway in the 

 air— for show. Had these columns, and the walls to which they are 

 attached, been also of painted pasteboard, their present purpose would 

 have been answered fully as well as by more solid materials. 



NOTES ON THE HYDRAULIC RAM. 



The invention of this singular engine is due entirely to the genius of the 

 celebrated Jlontgolfier, who made it known in 17U7 ; the peculiar simplicity 

 of its construction, as well of its mode of action, attracted the attention of 

 hydraulic engineers, and of mathematicians, and in 1801, Eytelwein 

 conducted a series of experiments upon a well digested plan, to develop 

 the power, the proportions, and other relations requisite to its greatest etfi- 

 ciency. The oscillatory motion of the water in the ram, and the alternate 

 action of the valves, indicate the physical causes which produce the eflfect 

 of this machine ; they are nevertheless still very far from being suffi- 

 ciently understood to furnish the basis of a mathematical theory. The 

 passive resistances, and especially those arising from the shock or blow 

 given by the valves, interpose difliculties in affixing their value, which 

 render any estimate of the whole dynamic effect almost impossible. Ex- 

 periment alone can instruct us as to the useful etfect it is capable of 

 aflbrding. 



D'Aubuisson de Voisins has given a succinct account of the researches 

 of Montgolfier and of Eytelwein, and these notes are chiefly derived from 

 it. 



The parts of a ram are, a pipe connecting a reservoir of water with a 

 case or chest containing two valves — an air chamber, and a rising or sup- 

 ply pipe. The pipe attached to the reservoir was by Montgolfier termed 

 the body of the ram, and the valve chest its head. Further description of 

 the construction of the machine and of its mode of action is unnecessary 

 here, as it may be readily found in every modern work on hydraulics. 



The largest ram ever erected was put up at IMello, near Clermont sur 

 Oise, by the inventor's son. Its principal dimensions were. 



Length uf body pipe . . .108 feet. 



Diameter of ditto . • • 4^3 inches. 



Weight of ditto . . • 3100 lb. 



Weight of head . . • 4-10 lb. 



Conteatsof air chamber . . • li gallons. 



The tail or stop Talve consisted of a horizontal metal plate pierced with 

 seven holes, each covered by a hollow ball l^ inch diameter ; it beats 60 

 strokes per minute. This ram worked under a head of water of 37 feet, 

 discharging 31 J gallons per minute, and raising 3^85 gallons to a height of 

 195 feet. The ratio of the useful eU'ect to the labouring force expended 

 was G53. The comparison of effect is made without taking into account 

 the velocity of the motion ; it is the weight of water raised to a certain 

 height in a determinate time. Calling p"this weight, and H" this height, 

 the effect is p"H". 



The corresponding force (P being the weight of fluid furnished by the 



stream in the same time, and H the height of the fall or head of water), is 



,,- H" 

 expressed by P H. — The ratio of these is consequently ~p~jj") or since 



9H" 

 p" : V :: q:Q, the ratio is y-jr 



The following table shows the ratio and the eflecl of ordinary rams. 

 The first experiment was made upon the ram constructed by Montgolfier 

 himself, at his house at Paris ; the second upon that erected by his son, 

 above cited ; and the others upon rams in the neighbourhood of Paris, 

 mentioned iu the Traite dts Machines, p. IGI. 



