GEOMETRICAL I'l ; 



153 



fx|.la<: v ; produce d e, the base of the door, directed 



.!!!,' l)illt \i ' no Wall 1> ttt } ; draw C b 



to p, also the p< . tli.-n tin- ; 



I il intorsiM-t tint piano of the wall in / / . j..m /, the bane 



miiimry. with tho VtunHhilitf poi. 

 will ii: 1 I..I.-.I- nf tin- u.iii ivr * per pc i 



in >n to VI**; thin will bo tho \ani-hmtf point. (,,r tlm 

 shadow i DM tin- w:ill i'. l>nrrti-il \,y vi**, unil through 



. I' i- ; almi, ilirtM-tfil by )>, draw r. 

 the shadow r k k will bo on thu wail i>, ami tint i ::minder 



In these lessons on Pernpcctivo we have endeavoured to 



i-xpluiu principles, rather than multiply example* ; ami i 



to carry nut <mr intention, tho subject* we have clioM-n have 



been those that would enable us to employ rules having a 



In conclusion, for whom, i* may b anked, are these Jessom. 

 in Perspective intended ? Are thoy to be studied only by archi- 

 tects and mechanical draughtsmi'i v these men 

 have the first interest in them, ax they satisfactorily prcvide a 

 means for rendering their work more truthful atnl 

 An architect and a painter may, in many respects, be famous in 

 tboir respective professions ; but if they are ignorant of the first 

 principles of design, which are founded upon the indisputable) 

 rules of Perspective, it is hardly possible they can have that full 

 power and freedom of expressing their ideas, which is so essen- 

 tially necessary for the success of their work. To the architect 

 a perspective drawing of a building from some particular 

 of view, showing how it will appear when erected, will answci 

 in every respect the purpose of a model ; while an intimate 

 acquaintance with angular perspective will relieve tho paintct 



general application. That which is of the first importance in 

 Perspective, and may be considered the foundation upon which 

 the whole science is built, is the projection of a point, or a 

 series of points, which, when nnited by lines, represent, accord- 

 ing to the positions of the points, the object required ; conse- 

 quently there can be but few especial rules. The infinite 

 variety of objects the draughtsman has to represent, with their 

 numberless forms and positions, may sometimes perplex him ; 

 but however complicated they may be, experience will teach him 

 that when in difficulties he must invariably fall back upon first 

 principles. 



We have thought it advisable, in stating our problems, to 

 give them under relative proportions, and to employ a scale of 

 measurement. Practically this will be found to be of great 

 advantage, as otherwise we should have given but abstract 

 forms, which might assist in explaining a theory, but for any 

 useful purpose would in a great measure frustrate the end we 

 have always kept in view namely, that of making these lessons 

 really serviceable to our pupils. 



B 



from the old, worn-out, and only resource of those who under- 

 stand but one vanishing point, the point of sight. But ther. 

 are others who have no professional necessity for studying 

 Perspective, to whom a knowledge of its principles is as im- 

 portant as it is to those who are called upon to practise it-, 

 believing it to be, as wo most certainly do, one of the most 

 necessary and important chapters in the grammar of art. No 

 one will venture to maintain that a thorough command of a 

 language can be acquired without a very close study of its con- 

 struction, knowing full well what the results would be ; and for 

 the same reason it would be dangerous for any one to pass 

 .judgment upon works of art, if ignorant of the principles of 

 that art. How many there are who do this, and give their 

 opinions in the most self-satisfied way on points of art of all 

 sorts ! But if we mention only one inducement out of many 

 we might propose, for studying Perspective as it ought to be 

 studied, practically, it would be that it enables us to under- 

 stand some of the beauties of art, to know its capabilities, and 

 to enter into its enjoyments. 



