128 
THE YOUNG SCIENTIST. 
pyramid, the cone, the cylinder, and the 
sphere. To these all natural and artificial 
objects bear some resemblance. For in- 
stance we find the sphere in the orange, 
apple, etc. The cone we find in the carrot, 
the trunk of trees, etc., and so on indefin- 
itely with the others. The importance of 
the study of geometrical figures and 
mathematical solids will be apparent to 
all, in the study of freehand and mechan- 
ical drawing. 
Let the student select for practice, say 
the cone, the cube, the pyramid, and cir- 
cular ring, at the right hand of the en- 
graving; draw them at least four times 
the size, and attempt to shade them. In 
shading with the lead pencil use a rather 
flat point. The parts in shade cover with 
a uniform tint, adding depth and strength 
gradually, following the same direction 
of line as in copy. This will enable you 
to see the outline assume the solid form. 
The art of shading, however, will be 
treated fully upon at a more advanced 
stage. 
We would, however, caution some at 
The cylinder will require some special 
attention in its treatment as a study, as the 
circle has to undergo an indefinite num- 
ber of changes in relation to its position 
with the eye. It is often difficult with 
both young and old to understand the 
plane of a circle or orbit. Perhaps as 
ready a method as any, is to take a ring 
or hoop, which at once describes a circle, 
or orbit, and turning it in various direc- 
tions in the hand show the alteration of 
the plane. It then assumes an oval form, 
more or less broad, according as it is more 
nearly level with the eye, or more be- 
low it. 
It appears as a straight line when ex- 
actly level with the eye. The following 
diagrams will convey this idea in a very 
simple manner. 
If the ends of a cylinder be presented 
directly in front of the eye, we have the 
circle. If it stands on end, and is viewed 
obliquely, we have the oval; its method 
of construction is indicated in Fig. 2. 
Here we have the top of the cube in per- 
spective; by drawing the diagonals we- 
THE CIBCLE AS SEEN FKOM DIFEEKENT POINTS OF VIEW. 
this point not to try too much at first, 
as the great object is to master an exact 
outline ; many fail by trying to hide this 
defect by a spurious and indiscriminate 
blending of shades, which the uneducated 
eye thinks pretty. This is death to all 
progress. Let the student continue to 
select other groups, and treat them in like 
manner, by which means alone he can 
become familiar with the proper forms. 
In drawing the box with the lid open, you 
will have a practical test of the former 
lesson. In every case the nearest parallelo- 
gram must be first drawn, then the whole 
figure to which it belongs. Auxiliary 
test lines will suggest themselves to find 
the angles of the next object, and so on. 
have at the point of intersection the 
centre, through which draw the bisecting 
lines. The oval can now be drawn in easy 
sections, observing that the half furthest 
from the eye is the smallest. This same 
law holds good on all sides of the cube, 
and the oval form that the circle assumes 
under all conditions, is to be determined 
by the parallelogram that a square de- 
scribes seen in perspective. 
Fig. 3 shows a straight line, as the eye is 
on an exact level with the object. 
Fig. 4 shows the cylinder in a horizontal 
position viewed from the end. 
All the other geometrical forms, thfr 
pentagon, hexagon, etc., etc., follow the- 
same laws of construction when drawn in 
