EDUCATIONAL PROCESS OF TRAINING AN ENGINEER. 573 
a direction in which, as a rule, he has not been trained in the preparatory 
schools. Especially is this true of the laboratory work, since chemistry, 
nnlike mathematics, is an experimental science ; and we often find that it 
trains the thinking powers of the student even more than do algebra, 
geometry, and trigonometry. 
Turning next to the subject of drawing, there are two objects to be 
accomplished : first, the execution; and, second, the power to express 
.deas by means of drawing, and power to read the ideas of others when 
expressed by the same means. Of course a certain amount of time will 
nave to be employed at the outset to teach the use of instruments, and to 
enable the student to perform the actual work of drawing. As soon, 
however, as he begins to do his work with a fair degree of accuracy and 
neatness, the attempt should be made to teach him the language of 
drawing, so that he can readily translate ideas into drawing, and vice versa. 
Now the mathematical theory of drawing is descriptive geometry ; 
hence he should at once be taught descriptive geometry thoroughly, so 
that he may have a thorough grasp of this subject. 
Free-hand drawing and lettering are both very important matters—i.e., 
free-hand drawing to such an extent as will enable the student to sketch 
easily and readily any part of a machine or structure, and to make neat 
and plain letters and figures. 
Next comes mechanism, which is, I suppose, the most elementary of 
the subjects that are commonly considered strictly professional work of a 
mechanical engineer. It deals with the combination of the means by 
which each of the machires of the world is enabled to accomplish its own 
special functions when the power has been furnished to it. It aims to 
make the student familiar with the methods by which these results are to be 
accomplished, and to teach him the principles governing them, so that he 
may undertake intelligently the devising of new arrangements, and avoid 
making impossible or undesirable combinations. The mathematics prin- 
cipally needed are algebra, geometry, trigonometry, and descriptive geom- 
etry ; but it will often save work and enable one to reach results more 
easily to have a knowledge of analytic geometry and calculus. After he 
has had his systematic study of mechanism, it seems to me that he ought 
to become familiar with the usual machine tools in general use; and, 
besides this, that he should make a study of some machines involving 
examples of decidedly complicated mechanism by actually examining and 
handling them. Then, again, we have a special class of problems in 
mechanism which concern machines that furnish power, as the mechanism 
of the steam engine ; but the one portion of the mechanism of the steam 
engine that requires special attention is the valve gear. Hence the 
student must have thorough instruction in valve gears and link motions, 
which shall drill him in the ‘mathematical principles for working out 
valve gears in all their details : and also he should be taught the different