Notes on an Easy Method of Camera Lucida Drawing 241 
One of the great difficulties in making drawings of consecutive 
portions of a large section is that the end of one portion only fits 
exactly to the beginning of the next portion when the plane of the 
drawing paper has been very accurately adjusted in the same plane 
as the object or the image. Using this method, one can move the 
section by hand or on the mechanical stage and leave a part of the 
section already drawn still in the field. This part can be fitted easily 
on to the drawing by moving the latter in the direction followed by 
the moved image. The outlines of both are clear and can be super¬ 
imposed quite accurately and easily, and then the drawing of the 
new portion can proceed. These adjustments only involve the turning 
of the mirror into the correct plane and this can be done rapidly, 
because it is only necessary to get a circle of light and not an ellipse. 
If two diameters of the illuminated zone at right angles to each other 
are equal the adjustment of the mirror is accurate. 
As examples of diagrams drawn in pencil or directly in ink by 
this method in from two to ten minutes readers are referred to my 
Textbook of Botany (Figs. 148, 150, 270 a , 395, 399, 400), while for 
detailed drawings occupying never more than one hour, and some¬ 
times only fifteen minutes for the pencilling, they may note the 
Figures 149, 151, 153, 154, 157, 268, 270 b, 274, 308 and 396 in the 
same volume. 
Botanical Department, 
Queen's University of Belfast. 
