Among recently designed instruments currently being evaluated is the 
profile plotter, a device permitting terrain profiles to be sketched from multiplex- 
type stereoscopic models (fig. 7). WIth this instrument a pencil attached to the 
multiplex platen is moved by varying the height of the platen as the tracing table 
Is pushed in the direction selected. There is no vertical exaggeration of the re- 
sulting profile, although the instrument could be designed to permit this. 
Figure 7. = The profile plotter, an instrument for sketching terrain 
profiles from multiplex-type stereoscopic models.