structure, though contrasted in age, and give to every one a name, 
such as a young plain, a mature or middle-aged plain, these terms 
bring certain well-marked conceptions before us., conceptions that 
have been elaborated in our study of the type or standard of 
reference, and we readily form a mental picture in which all the 
many essential features of the region described are clearly appre- 
ciated. An adolescent plain, for example, is a surface of broad 
even uplands, here and there trenched across by streams which 
follow valleys of moderate width ; the general continuity of level 
from one inter-stream surface to another comes to mind ; the rela- 
tive scarcity of the smaller stream channels ; the relation of the 
region to its fellows of greater or less age. 
It is immaterial what names are used for the present in describ- 
ing plains and plateaus, for none as yet are authoritatively ac- . 
cepted by geographers, but it would be to our common advantage 
if experiment were made on the use of a larger set of terms than 
is now commonly employed. The important point is that terms 
based on natural relationship should be used, and that they 
should be familiarized by the study of type forms. Experiment 
will alone decide what term shall be finally adopted. My own 
experience with students of undergraduate age has shown me 
that the idea as here outlined is a valuable one, and that the terms 
here employed are suggestive and satisfactory. I am very de- 
sirous of hearing the experience of others in the same experi- 
mental line. 
A few words may be said as to the method of using the 
models, a method that seems to me adapted to young as well as 
to more advanced scholars. A series of models is laid out on 
the tables of a room which, in the schools of the future, may, I 
trust, be called the geographic laboratory. The students are 
seated near them, an^i each one is asked to describe what he sees ; 
to note if he can recognize any features of the miniature land- 
scape that are already familiar to him from his own observation. 
He is then told to try to draw a map of the surface represented, 
or a part of it if the whole is somewhat complicated. More or 
less aid must be give here, as so many students are untrained 
in the simplest delineation. When the map is drawn, show the 
