DESIGN. 



DETACHMENT. 



490 



the thickness of the walls and floors, the heights of the rooms, the 

 forms and profiles of ceilings, whether plain or decorated, flat, coved, 

 or arched ; also the exact forms of domes and skylights. In fact it 

 exhibits all the separate elevations of the rooms intersected by such 

 plane, that is, the elevation of that side of them which faces or lies 

 behind the plane of representation. In addition to the particulars 

 just enumerated, we are by this means made acquainted with a variety 

 of others, in regard to which a plan cannot be made to afford any in- 

 formation. The thickness of the walls may be ascertained by the 

 plan as well as by a section ; so also might the height of the rooms be 

 expressed in the former by means of figures, as the other dimensions 

 generally are ; and the form and size of the windows may be learned 

 from the elevations ; still we should not know what are the heights of 

 the doors, how they are pannelled and decorated, nor what is the form 

 of the chimney-pieces, &c. ; nor be able to judge so well of the general 

 proportions of the apartments. Besides which, sections may be made 

 to show much more than what belongs to the architecture alone, for 

 there are many instances in which furniture, pictures, and other deco- 

 rations and fittings-up, are introduced ; and unless this be done, a 

 section is apt to have a naked appearance, except the architecture 

 itself be particularly interesting and rich. For detailed and filled- 

 up sections it is usual to employ outline, with the walls and floors 

 shaded, the former as more solid being made much darker than the 

 latter. When, on the other hand, the elevations of the rooms them- 

 selves are shadowed, the thickness of the intersected walls, &c., are 

 left white, in order to prevent confusion and exhibit the profiles better. 

 It should be observed, too, that ha sections of this latter description, 

 it is the practice to throw a shadow from the aide walls and ceilings of 

 the rooms, as if it were a model of the building really cut through ; 

 thus producing an effect both disagreeable and unnatural, and by no 

 means assisting towards rendering the representation more intelligible. 

 Indeed indispensable and interesting as they are, sections are a far 

 more conventional mode of drawing than elevations, because they re- 

 present a building as it never can be seen at all, except where the 

 front of a house has been taken down for the purpose of rebuilding 

 it, while the floors and partition-walls are left standing; in which 

 case any one may obtain a good idea of the nature of a section, but 

 of one seen iu perspective. Besides general sections showing the whole 

 of a building from top to bottom, there are frequently partial ones, 

 showing only the rooms on one floor, or even a single room, when it 

 is desired to show it on a larger scale than could conveniently be done 

 any other way. Or instead of this, recourse is sometimes had to a 

 plan of the room with each of its elevations or sides drawn around it, 

 as if laid down flat on the ground, by which means the whole of the 

 apartment is described ; for the ceiling may be represented on the 

 plan itself. Horizontal sections again are occasionally made use of, in 

 order to show more accurately than can be done upon a plan, not only 

 the ceiling and its ornaments, but the soffits of entablatures, of 

 window recesses and door-cases, also the capitals of columns and their 

 projection. 



Although not in general use, there are likewise many other modes 

 and combinations which deserve to be pointed out. One of them is 

 that of elevation and section united ; that is, one half the drawing 

 shows half the elevation, which, as far as understanding it, fully 

 answers the purpose of an entire one ; while the other half shows half 

 the section. Another is that of sectional perspective view, which, while 

 it serves the purpose of a section in regard to showing the exact form, 

 profiles, and measurements, on the first plane, intersecting the struc- 

 ture, gives also a picture of its interior just as it would appear in any 

 other drawing of the kind ; the only difference being, that in this case 

 the drawing extends beyond the interior, while in other views it is 

 bounded by and confined within it. It is hardly necessary to observe 

 that such a mode is suited only for showing a single space, and not one 

 divided into separate rooms. It is exceedingly well calculated for dis- 

 playing the interior of a portico, as it admits of the situation of the 

 columns in front being shown by the foreground being made a per- 

 tpeetive plan. 



Besides the usual plans, elevations, and sections, there must like- 

 wise be detail* or parts at large, answering in some respect to what are 

 termed working drawings ; since without these we judge only of the 

 general design, but not of its minutiae and finishing, whether belonging 

 to decoration or construction : and far more may be learned, and that 

 too more satisfactorily, by studying a single good example thoroughly, 

 than by looking at many which are only imperfectly described. It is 

 therefore to be regretted that published designs, unless they happen 

 to be those of actual buildings, are so exceedingly defective in this 

 respect, generally showing no more than a couple of plans with one or 

 two elevations, while, although so very essential, sections are entirely 

 omitted. In order to illustrate a subject properly, not only should 

 there be a plan of every floor and an elevation of every side, but 

 sections, both longitudinal and transverse, and as many of each as the 

 nature of the plan may require. 



Having done thus much to show the whole anatomy of the structure, 

 we may then provide perspective views both of the exterior and prin- 

 cinal parts of the interior, in order to show the character and effect, 

 which, without such drawings, can be judged of only piecemeal, and 

 inadequately even by those who perfectly understand the others. 

 Yet however satisfactory as a representation, a perspective view 



of an interior must still leave much to conjecture, as one of the 

 sides or ends of it cannot possibly be shown, while of the others two 

 will be more or less foreshortened, so that if there be deep receding 

 parts in them, they can be but imperfectly seen, perhaps may be 

 quite misunderstood; or can be well understood only by the aid 

 of plan and section. In many cases, therefore, an interior would 

 require two or even more perspective drawings in order to show it 

 completely. But with every part of the building thus fully made out 

 and described in drawings, the whole may be understood as well, in 

 some respects even better, than by a model of it ; for besides that the 

 latter can do very little towards showing the interior certainly not its 

 effect, -there is this drawback attending it, that it conveys no idea of 

 situation or locality, and that, instead of the eye being confined either 

 as to due distance or height, it views it from points from which the 

 building itself can never be seen under any circumstances. Neither 

 has it the accompaniment of sky, background, foreground : a model 

 exhibits the mere building alone as it is, certainly, yet not as it 

 appears ; for it is seldom any attempt is made to give the proper local 

 colouring at least to do more than merely hint at it. By means of 

 perspective views, on the contrary, provided they be sufficiently nume- 

 rous and judiciously chosen, and not deceptively embellished with 

 effects of rare occurrence, we may obtain a most accurate idea both of 

 the architecture and of all its local accompaniments and accessories, 

 whether favourable or the contrary. Of bird's-eye views of buildings 

 we have said nothing, both because they are now seldom made use of, 

 and because we consider them not only most awkward, disagreeable, 

 and unnatural representations in themselves, but as altogether super- 

 fluous, if a building is properly described by the other modes, or even 

 by a block-plan and elevation alone. 



DESIGN, SCHOOLS OF. [SCIENCE AND AHT, DEPARTMENT OF.] 



DESPOTISM. [MONARCHY.] 



DETACHMENT, in military affairs, is a portion of an army or 

 body of troops detached and sent on a particular service. It may 

 consist of thousands of men, cavalry, artillery, and infantry, or a small 

 portion of a company. The former description of detachment, namely, 

 one that will materially weaken the main body of an army, has often 

 been made with good results, and more often with bad ones ; it is in 

 fact one of the most difficult and dangerous problems of strategy, 

 depending, as it does, for its success in many cases on the fortuitous 

 concurrence of many eventualities, the non-foreseeing or reversal of any 

 one of which may upset the best laid plan for the co-operatioii of the 

 main body and its detachment, and allowing each to be taken in detail, 

 lead to the most disastrous results. Jomini, in his ' Precis de 1'Art de 

 la Guerre/ treating this as a mixed operation which partakes at once 

 of strategy and tactics, has laid down very clearly nearly all that can 

 be said on the subject, and to his work the reader is referred, as the 

 following article can only pretend to exemplify some of the most open 

 advantages and defects of detachments. 



A general is so often compelled by necessity to make detachments, 

 and on the proper handling of them so much depends the success of a 

 campaign, that one cannot but consider this one of the most 

 important and delicate operations of a . campaign. " En effet," says 

 Jomini, " si rien n'est plus utile qu'un grand detachement lorsqu' il 

 est fait a propos et bien combine', rien n'est plus dangereux quand 

 il est fait d'une maniere inconside're'e." The very employment at all 

 of a detachment, except in those cases where it is meant to rejoin and 

 co-operate with the main body at the critical moment of a general 

 action, appears to be contrary to the cardinal principle of strategy and 

 tactics to act with superior forces on the decisive point, and yet there 

 are circumstances under which they are indispensable. The general 

 employment of detachments may be classed under the following 

 heads : 



1. The employment of great detachments, almost separate armies, 

 not in the principal zone of operations, but with the object of creating 

 diversions on more or less essential points. This seems the most 

 indefensible use of detachments, one in which English forces have 

 often been employed, and which, against a great general, such as 

 Napoleon, were utterly thrown away; for instance, in 1805, Napoleon 

 occupied Hanover and Naples. An English and Russian army was 

 formed to drive him from Italy, and an English, Russian, and Swedish 

 army to operate in Hanover. Nearly 60,000 men being employed in 

 these two detachments, Napoleon, disregarding them, ordered St. Cyr 

 to join Massena on the high Adige, where, based on the Adige and 

 Mincio, and in a very strongly fortified position, he was to oppose the 

 Archduke Charles, whilst Bernadotte quitting Hanover joined him in 

 time to take part in those overwhelming operations about Ulm and 

 Austerlitz, after which Italy and Hanover were easily retaken. On the 

 other hand, a detachment of this description would, in the civil wars 

 of 1793, Jomini considers, have produced decisive results if thrown 

 into La Vende'e. 



2. Large detachments in the zone of operations to cover important 

 points, to carry on sieges, to mask fortresses, or to protect fines of 

 operations. 



These may be termed permanent detachments, acting perhaps 

 during a whole campaign in their own zone of operations. There are 

 again temporary large detachments formed for any of the following 

 special objects bearing immediately on the grand objects of the 

 campaign : 



