S74 



instanced. 



ON TH« CAMERA LUCIOA. 



When I had taken my stand, arranged my paper, and 

 fixed the camera lucida upon it, I had, upon looking into 

 the eye glass, a distinct view of the whole scene, as perfect 

 as the instrument would represent it; but a different ar- 

 rangement was necessary, before I could have a chance of 

 copying, or, if you please, drawing it: I was to alter the 

 position of the eye glass, so that I should, in the upper 

 part of it, sec such of the objects as I was to imitate; and, 

 in the lower part, a distinct representation of the paper 

 and pencil with and upon which i was to draw; these two 

 divisions will admit of different proportions, but, to speak 

 in general terms, we may say, the upper part contains a 

 correct view of part of the objects that are to be drawn, the 

 ower part contains a correct view of the paper on which 

 hey are to be drawn, and the pencil by which the drawing 

 is to be made: the operation to be performed is, to look 

 upon the representation of the objects, and the represen- 

 tation of the pencil and paper at the same moment, and to 

 copy exactly upon the lower, what is seen upon the upper 

 part of the object glass ; this every man will do in propor* 

 ' tion to the power he has of imitating the forms of objects 

 Difference be- that are placed before him. The essential difference between 

 tween the two. ^h e caDiera obscura and the camera lucida is, thatthe former 

 fixes upon the paper the whole of the picture at one view, 

 and the artist has only to pass his pencil over it to render it 

 permanent, which he has the power to do with more cor- 

 rectness and expedition, and equal facility, as if he was 

 drawing without the use of the instrument. The camera 

 lucida, on the contrary, places before the eye a certain 

 portion of the objects to be imitated, and a certain portion 

 of the paper on which the imitation is to be drawn: the 

 difference between the two operations will be exactly as 

 the difference between tracing and drawing against the 

 window, and copving the same drawing if placed before 

 you upon the table: this is the difference upon a view of 

 the whole proceeding, but, upon descending to minutia?, 

 other circumstances bear still more against the camera 

 lucida. 



The circle Fig. 2, PI. X, contains a representation of so much 

 of the view as can be seen at the same time, with so much 



of 



The process 

 farther de- 

 scribed. 



