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any ^ no °l at an age in which he cannot have imbibed inar chit ^ ree su ® c ' ent of a polite and liberal education, theof g ct ural pupil, frequently with no knowledge whateverll 7’ never acquires any beyond the mere manualbi s jg 1 y drawing circular and plain lines ; abandoned byinto D aster while yet scarcely arrived at manhood, forcedof / emature and profitless practice with all the expensesthe arate es tablishment, it cannot be wondered at, thatcau Se °‘ es cent architect sometimes has, in after-life, bitterled },j. 0 re pent the circumstances and the rashness, which«olei y j,* 0 ac< l u i r e practical design and practical construction,fepont ^ f 1 ' 8 youthful failures ; for it is then, with deepHi^ /' c ®> that he perceives the confusion of styles intoHicij , e las fallen, the whole chronology of gothic archesin the same fa 9 ade, the mixture ofPlicity 0 f rms an< l luxury with the severe and elegant sim-he ?, the Greeks ; in many a breaking-up and fracture,be ha 3 fortification to find that inventions upon whichl,1Ve nto > * ea f° r eternal duration, have not survived theirRfafiy,., a f uin ; that he has formed his pinnacles withs oi]y Cf; outlines, as if Rosslyn chapel or some other impureJis col u 6re on ly pursuit; he regrets that he has placed"e rer, r „| nn8 opposite apertures, instead of opposite piers ;P°ise, ),; s ttla t> from false bearing, want of plumb and equi-, ejc Peri en S Wor k is so fractured, that even a man of moreaf e, himself cannot restore it ; he perceives too

P I etei >defi “? Peonage of mean and fragile stone, and^hled go su ^ st ’tutes for it, 1 lis reliance on bad timber, has' e Perc e ; 6t .8 to the wreck of his country’s architecture ;i^tical Ve ? Wlt h deep mortification, that his want of mathe-led mec hanical skill, both theoretical and practical,t*Peri eric lln to perform that which a professor of morebfust f r w °uld avoid ; broken arches, tie-less roofs, walls^ Stoan^ 1 la Sht position, partitions falsely trussed,

?!§ht ' n ® beneath loads which, formed otherwise, they

i lll 'sin ,T e horn • .

d‘ oth Ir ° m t ^ le building being carried up piecemeal,yj?*st er8i ® r causes—these are a few of the faults andf *' e had IC1 * n a l' ter times make a precocious practitioner^ himlr tUdi , e<1 five or ten years more, before he haddJP'is Waslw*. 1 ” 8 employer’s property.”

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1 in all a"”* 1 - 6 unflinchingly, and a foundation which

'Uffs „ a ' re ctions from want of sufficient spread to thev ° ’ or f rom ,• , • • . * •_i

t° q lJa ip 0t bbe case formerly; men endeavoured in thoseup «...y themselves for the Dractice of their Drofession.

a r '£ stnri" J Ulem selves for the practice of their profession,cli c hitect s y ’ ^ ract ’ ce > anf l unceasing diligence,bniters v. . atnon g the ancients, were highly accomplishedof "f filled in all the geometrical and mechanicalSig clai m t l . r i ar| d in this country they have had(.q.that ti ° em * nenc e as late as the reign of Queen Anne .

Percp ne \k° Wever ’ a gradual declension of the art ishL °f ^ a h public edifices, as well as in all

Sti>» • u Rh '^ctural literature,a »_ l, Wt. , ave Uing adds to the a

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n g adds to the accomplishment of a judicious

ob 8er t m0n g t' le b east °f the necessary qualifications;

tba n h P , r w ’tl lay up greater stores of knowledge attfavp. 'b the ' V l0 ,has travelled, with inferior abilities ; and,be ^.Qg, a c®hitect have no farther views, than that of?ltifti ’ m r<lerto P r °duce what he calls drawings of taste,'b'Pr St % lo*°" * nstan ces, become ostentatious, and willth e tle good opinion of his employers. Travelling’'Vr ar, d re ra , an °b science, but inflates the sciolist with. As'?, 1011 tint, i. ers him ten times more a subject of com-Sn, ta ose p a ” before.

’ 8 Placed 8 car P ent ry which are objects of descrip-tion .^cd to p Ul ? der their proper denominations, the readerb* a Uapf. . ac i particular term, for further information

ul subject.

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DESCRIPTIVE GEOMETRY , the art of representinga definite body upon two planes, at right angles with eachother, by lines falling perpendicularly to the planes from allthe points of the concourse of every two contiguous sides ofthe body, and from all points of its contour ; and, vice versa,from a given representation to ascertain the parts of theoriginal object.

Descriptive geometry may therefore be consideredsynonymous with orthographical projection, upon whichsubject, with the exception of a treatise by Mr. P. Nicholson,(first published in 1795, and re-published with improve-ments in the year 1809), nothing had appeared in theEnglish language, until the publication of this Dictionary.

About the year 1794, the celebrated Monge, who has beencalled the inventor of descriptive geometry, published inFrance his Geometrie Descriptive, one of the most elegantand lucid elementary works in existence. Previous to theappearance of this work, the science of perspective andmany other applications of geometry to the arts, had requiredisolated methods of obtaining lines, angles, or areas, describedunder laws not readily admitting of the application of algebra,and its consequence, the construction of tables. The des-criptive geometry of Monge is a systematized form of themethod by which a ground-plan and an elevation are madeto give the form and dimensions of a building. The pro-jections of a point upon two-planes at right angles to eachother being given, the position of the point itself is given.From this it is possible, knowing the projections of any solidfigure upon two such planes, to lay down on either of thoseplanes, a figure similar and equal to any plane section ofthe solid.

This necessary and neglected part of education, had beenalso much cultivated by Mr. Nicholson, and with suchsuccess, that his works have always been referred to bysucceeding writers as authorities. In addition to the treatiseabove mentioned, and also some parts of the carpentry inRees’ Cyclopaedia ; the numerous valuable articles in thisDictionary attest the sound practical knowledge of the writer,and his perfect acquaintance with the subjects on which hehas written. It is due to his memory, to state that he hadat that time no knowledge of any foreign work on DescriptiveGeometry , and that the treatise by Monge did not fall intohis hands until the year 1812. While strongly recommend-ing that work, however, to the study of all those whoare desirous of attaining truth in delineation, he con-sidered his own views, differently conceived, as undoubtedlythey were, from those of Monge, to have equal claims tooriginality.

As we are desirous of omitting nothing that may tend toenlarge the bounds of science, we shall here insert so muchof Monge’s work as we conceive to be conducive to this end,referring Mr. Nicholson’s own ideas on this branch of geo-metry, to the article Projection, a name better understoodin this country than that of Descriptive Geometry .

To facilitate the knowledge of this subject, the readershould be well acquainted with the eleventh book ofThe Elements of Euclid , which treats particularly of planes,and the manner in which solids are constituted.

“ Figure 1.—If from all the points of an indefinite rightline, however situated in space, we imagine perpendicularsto be dropped upon a given plane, lhso, all the points ofthese perpendiculars will fall upon the plane in another inde-finite right line, a h, for they will be all comprised in theplane described by ab, perpendicular to the plane mso,and can only meet the latter in the line of intersection com-mon to both planes, which is a right line.

« The right line a b, which passes through the projections