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would follow the description of the remainder of the operation, we h bered the diagram with more letters of reference; the lines showing similar applications of the process for all parts of the curve. The fact of the shadow may be completed by taking the line DD as the trans ellipsis, and finding the semi-conjugate axis Oa by the means above descri a semi-ellipsis in form, inasmuch as it is the projection of a section of a he example is applicable to the shadow of a cylindrical niche with a hemisph line NN shows the shadow of the portion of the head, and the remainde the mere intersection of lines in the direction of the light from different of N, of which enough has been already given in the previous examples to cation intelligible.

2476. Fig. 852, is the representation of a pediment wherein the section

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wherein the upper story is occupied by an attic in the centre, against which, on each flank, the sloping roof is terminated. aa on the plan in the direction of the light, produced to intersect the hip at b, gives, by a vertical to B on the elevation, the direction BB of the shadow thereon ; and BB cut by A A in the direction of the light, the length BA of the line of shadow, which may, by letting fall the vertical Aa, determine the length aa on the plan. The line of shadow ac is determined by letting fall a vertical from C, where the line of shadow is intercepted by the hip of the roof; and from c the shadow will be found on trial to return as shown in the diagram. E

Fig. 855. and D on the elevation are found, as seen in previous examples, in ee, and d on the plan, and their shadows at e'e' and d'.

2480. What is called an attic base is given in plan and elevation by fig. 856. thod of obtaining the shadows thereof in plan and elevation is now to be explained. It is an example which constantly occurs in architectural subjects, and should be well studied and understood. The operations requisite for obtaining a representation of the lines of shadow of the different mouldings in this example depend upon the principles developed in the preceding subsections. The lower portion of the figure exhibits the plan, and the middle portion the elevation of the attic base in question. The uppermost portion of it presents three sections of the mouldings of the base in question cut in three different places parallel to the direction of the light. This last portion of the figure is not absolutely necessary, inasmuch as the profiles in question might have been obtained upon the elevation; but we have preferred keeping it separate to prevent a confusion of subsidiary lines. There is moreover another advantage in thus separating the parts from each other, namely, that of immediately and more distinctly seeing the lines at each selected place, in which the rays of light separate the parts actually in light from those in shadow; and where the student is likely to meet with matters of perplexity, nothing should be left untried to save his time, and, what is often more important, his patience. The mode to be adopted is as follows:

Make on the plan any number of sections a'a'a'a', U'b'b'b' in the direction of the light, and draw on the elevation the corresponding sections aaaa, Lübb. LL being the direction of the light, draw parallel thereto tangents to the curves of the convex mouldings, and the bounditries of their shades will be obtained, as will also those of their shadows, by continuing them from such boundaries till they cut the other parts in each section, as will be more especially seen at cc. It will be recollected that in our first mention of the projected representation of the line of light and shadow we found that it was an angle of 54° 44' of the diagonal of a cube. This angle is set out in xyz on the plan. We have therefore another mode of finding the boundaries of shade and shadow on the moulding, by developing the sections a'a'a'a', b'UU'V', &c., as at A, B, and C, and drawing tangents yz to the convex mouldings for

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Fig. 856.

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boundaries of shade thereon, and continuing them, or otherwise, for the shown in the diagram.

2481. In fig. 857., which represents the capital of a column, a similar method is used to that last mentioned for obtaining the shades and shadows, by means of a'a'a'a' and V'B'b'b', which are shown on the elevation by aaaa and bbbb. We apprehend this will be understood by little more than inspection of it.

It is obvious that the means here adopted for obtaining the lines of shadow are precisely similar to those used in the preceding example. In this, however, the sections of the capital parallel to the direction of the light are made on the elevation, and it will be seen that many of them are not required to obtain an accurate boundary of the lines of shadow sought; for after having obtained those points from which the longest shadow falls, and on the other side those where the line of shadow commences, a curve line of an elliptical nature connects the points found. If be made be on a large scale, it may then be worth the architect's while number of points wherefrom the shadow is to be projected, so as to prod possible accuracy in the representation.

2482. The shadows of an Ionic capital are given in fig. 858. The shad on the column is obtained by any number of lines A A, BB, CC, &c. fi

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parts and verticals from their corresponding ones aa, bb, cc, &c. on the pl the shadow of the capital on the wall. In this example, as in those immed the employment of sectional lines parallel to the direction of the light is The use of them is most especially seen in the example of the Corinthis follows. As a general rule, it may be hinted to the student of sciography culties that may occur, they will be most expeditiously and clearly resc of the sectional lines, whereon we have thought it proper so much to dilat

2483. The Corinthian capital in fig. 859. will require little more th understand the construction of its sciography; and all that we think nece larise are the developed projections A, B, C, D, E, F of the abacus and the the termination of the shadows at angles of 54° 44', as explained in fig. respective depths on the elevation.

There is another method of arriving at the result here exhibited, by lines parallel to the direction of the light through the different parts a

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capital on its elevation, as in fig. 857., and such was the mode we were formerly in the habit of adopting. It however induces such a confusion of lines, that we have long since abandoned it, and have no hesitation in recommending the process here given as the best and most likely to avoid confusion. It is of course unnecessary, in making drawings, to project more than the shadow of one capital, as in a portico, or elsewhere, similar capitals, similarly exposed to the light, will project similar shadows, so that the projection on one serves for the projection on all of them.

2484. For instruction upon the mode in which reflected light acts upon objects in shade and shadow, we must refer the learner to the contemplation of similar objects in relief. The varieties of reflexes are almost infinite ; and though general rules might be laid down, they would necessarily be so complicated, that they would rather puzzle than instruct, and under this head we recommend the study of nature, which will be found the best instructress the student can procure.

Sect. IV.

GENERAL PRINCIPLES OF COMPOSITION.

2485. The end of architecture, without whose aid no other art can exist, is not merely to please the eye, but so to provide against the changes of the seasons as to be serviceable to man. Pleasure to the eye may, however, result from the useful, well combined with the beautiful modifications whereof it is susceptible. It is in combining thus that the genius of the architect is exbibited. The art of decorating a well-proportioned edifice is a very secondary and comparatively easy part of his work, though requiring, of course, the early cultivation of his taste and an intimate acquaintance with the parts, whereof this may be taught and that acquired; but the distribution and arrangement of the several portions on the plan, upon which every accessory is dependent, requires great knowledge and considerable experience. And in this is involved not only the general conveniense and effect of the building, but what is of much consequence to the proprietor, the cost of the work. None but those practically conversant with the planning of a building would believe the saving that may be produced by proper distribution. In the case of many external breaks, for instance, much addition arises in the length of walls enclosing the edifice, without generally increasing the convenience of the interior, but always when the elevation comes to be adapted to the plan, with the certainty of breaking up the masses, and destroying the simplicity of the effect. This is mentioned merely as an instance of simplicity of plan always producing wimplicity of section and elevation.

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2486. All ornament in architecture is non-essential, inasmuch as the by the eye is not its end. To public and private utility, the welfare and viduals, which are the ends of the art, every other point must be sacrificed when these have been accomplished that we are to think of decoration. related of a certain nobleman, who, having boasted to a friend of the beau of his house, which within was exceedingly ill contrived, was told that he would do well to take the house opposite, that he might be thus always Those who make the internal parts of an editice subservient to the pro and adjust their plan and section to the elevation, must be considered end of less importance than the ornament of the building. Those w mode produce little variety in their designs, which, numerous though of but few different combinations, whilst those that result from the natural the façade subservient to the internal parts, which the plan and sect susceptible of infinite variety and decoration.

2487. It is not, however, to be supposed that we are, in what has been the student's neglect of careful composition and adjustment of the faça adaptation of the different fronts of the building to sort with the inter the greatest care should be bestowed. It is from these his reputation is li cause they are the parts most susceptible of comprehension by the public. T upon every succeeding day's experience, find that the two objects are no but if such a case, which is possible, arise, he had far better sacrifice the ing first the comforts of those who are to inhabit the house, and then of those who are only to look at it.

2488. Durand has well observed that compositions conducted on the must please.“ Has not nature," says that author, “ attached pleasure to t our wants, and are our most lively pleasures other than the satisfaction of ing wants? These wants are better satisfied in the interior distribution of in the exterior.” Who leaves the Pantheon without more satisfaction ti from the view of the portico, fine though it be? Again, faulty as are bot St. Paul's, will any one who understands the subject aver that he has rec sure from their respective façades than from their noble interiors ? The pl tions produced by both are entirely dependent on their interior distribution find that in the former of these buildings there is no mockery of a dome, exterior being as far dependent on each other as the circumstances of con permit, whilst the dome of the latter is worse than a mockery, the inte domes having nothing in common with each other, the last being no mo leaded appurtenance to the fabric, Wren, with all his greatness, for great into nothingness by the side of Michael Angelo, although the external forn London be more elegant than that of the Vatican. This is a strong but ne tration of our opinions, the good sense whereof must be left for appreciation who, we doubt not, on a little reflection, will concur with us.

2489. In ninety-nine cases out of a hundred the student will find that a g of his plan leads him, with anything like ordinary tact, to the composition and good elevations, far better, indeed, than he could arrive at by pursu course. In domestic Gothic architecture, this is notorious, for in that a r tion of the openings would often produce the tamest and least pictures Gothic architects placed windows internally where only they would be ser them take their chance in the exterior. It is not to be understood, because rather outré, that this method will exactly suit the principles of composition tecture ; but it is well known to practical men that a required opening in a instead of being a blemish, may he converted on many occasions into a bea is incontrovertibly true that distribution and disposition are the first obj engage the architect's attention, even of him whose great aim is to strike ornament, which can never please unless its source can be traced to the and economical distribution of the leading parts. Theorists may be laughe not move us, nor diminish our regret to see many architects without any o that whereon, in an inverted position, their own wild fancies are grafted. stated be true, and from the nature of things we cannot imagine a contu upon our observations, the talent of the architect is to be estimated, as observes, according to his solution of the two following problems: – First. For a given sum, as in private buildings, to erect the most conv

able house for his employer. Second. The requisites in a building being given, as in public building

the smallest possible expense. 2490. An investigation of all the modes of accomplishing these deside fully effected in a work of much larger extent than this; but we have, parts of our volume, so prepared the reader, that he will not generally be at of the construction of a building, whatever its nature or destination.

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