- 454 
The new method, however, offers new opportunities not 
only for obtaining the elevation data required for mapping but also 
for charting the planimetry and determining the scale. This very 
significant fact also opens up new possibilities for aerotriangulatiol 
and it would appear that the synthesis of the aerotriangulation metho 
and the radar profile method might provide the long sought solution t: 
the problem of the provision of control points for detailed mapping o! 
a small or intermediate scale. 
Obviously the radar profile offers an immediate solution 
to a great many of the technical problems connected with topography 
and it is unfortunate that they cannot all be dealt with in this 
brief outline. 
A further significant fact about the airborne profile 
recorder method is that it permits in actual operation a very elastic 
relationship between the altitude at which the photographs are taken 
and the profile flights flown, thus achieving a high degree of 
economy in photogrammetric mapping. 
As I mentioned earlier, the radar profile method has 
already developed beyond the initial stages and is now being used, 
as well as other methods, to overcome many of the problems encountere: 
in map production. This does not mean, however, that its development 
is by any means complete. On the contrary, a number of projects now 
in hand are aimed at the improvement and perfection both of the instr 
ments used and the procedures followed, and the active participation 
of photogrammetrists in this work will be indispensable if our growin, 
hopes for the radar method are to be fulfilled.