164 
MAURICE G. MEHL 
A long stick with a hole the size of a pencil bored at midlength 
may be moved about in a plane formed by the edges of a frame 
about the model and somewhat higher than the latter. The 
pencil, if fitted closely, may be ^^set’^ at the proper distances 
above the base of the model and the corresponding contours 
traced. 
Fig. 6. An apparatus for contouring models and illustrating the use of con- 
tours. Constructed in the laboratories of the department of geology, Denison 
University. 
ADVANTAGES OF THE MODELS 
Contrary to what might be expected, the models promote 
speed of contouring the field data. The average data may be 
modeled and contoured and the contours transferred to paper 
or tracing cloth in less time than is usually required to puzzle 
out the best interpretation after the ordinary manner. 
The model has been found an excellent aid not only in visualiz- 
ing the data for the geologist but in explaining the nature of the 
configuration of the beds to those not familiar with contours. 
As a sales argument, several oil companies have found the models 
invaluable. 
