2 PER-SPECTIVE DRAWING. 



May be very give four or five close lessons, I have generally seen my eirJ 



SI y acquire Q^jajj^gj jq jIj^j^ great satisfaction, without ever shewing them^ 



the Jesuits, or any other voluminous treatise ; books that have 



hindered more from the study of art, than they have ever 



made artists; for a moment's consideration on this subject will 



convince any mind, capable of reflection, that, to accomplish the 



general ends that even most painters have in view with respect 



to that art, it is only necessary to know the use of ihe points qf 



Hewhocan put sight and horizontal line. For while men have agreed to avoid 



horizontal and \yQyQ\ \\^^^ j^^ all their constructions that are intended for use or 



perpendicular . , ,, i i i > i r \ l. 



lines into per- habitation, we shall only want as much knowledge ot the art 



spective, will ag will enable us to put these into perspective, and to assit us 

 do every thing ^^ ^^'^U before, by practice, we have attained a correct eye j 

 else. for practice, daily practice, will soon do all the rest, even by 



barely drawing the interior of a large apartment or gallery, 

 with the objects continually before us in common use. 

 Simple coniri- To save time, however, and to imprint the few lessons ne- 

 vance for Va- . , /- . t i • 



nishiHg-Lines. cessary to be given on the raind of a learner, I have, some tmie 



back, made use of the following simple contrivance, which I 

 now send to you, as the most likely means of universally pro- 

 moling this necessary preliminary study, where the first gene- 

 It is a ruled pa- ral principles have been instilled : — Take a sheet of paper of 

 P®'' ^^^^^"^ ^^^ an octavo size, and rule it with very black ink, from A to B 

 (Fig. 1, Plate 1). This represents the horizontal line; then 

 fix a point in the centre, at C ; this we will call the moveable 

 point of sight : afterwards cross it, as in the plate, with as 

 many diagonal lines as you please; and thus you have an in- 

 strument prepared that will be a sure guide to an inexperienced 

 eye, in taking the perspective lines of all objects placed at 

 right angles; such as streets, buildings, churches, apartments, 

 &c. by mearly placing it under the leaf you mean to draw them 

 on from nature, so as to see them faintly through, as boys do 

 their writing-copies, when young and inexperienced. 

 A correspond- But, to make this instrument more complete, we should add 

 'Ivs'liavhie si- ^ P'^^^ of glass of the same size as the leaf of the drawing- 

 mil^r lines. book, on which the like dark lines should be drawn so as, by 

 holding it up perpendicularly, we may see, and, as it were, 

 render tangible, the truth of perspective lines ot buildings ; and 

 for those whose sight is bad, or for very young people, it vv'ould 

 — or a copper- not be amiss to take a copper-plate of the like dimensions, and 

 ^n^"^rinVlines' ^^*'^^ ^ ^'"^ needle gently scratch out the like lines, in which 



