POSSIBILITIES OF AERIAL PHOTOGRAPHIC SURVEYS. 
species, quantity, and quality of the timber on an area, information 
which is, as a rule, given by the ordinary ground surveyor; but this 
would not constitute a serious objection, as the map itself would be very 
speedily obtained, and with its assistance the task of the local forest 
or working plans officer in making the inspection necessary to supply 
the missing information would be greatly facilitated. 
‘It is, however, only reasonable to point out that the initial expense 
of establishing the system would be very considerable, involving as it 
would the erection of hangars and workshops, the creation of main aero- 
dromes in suitable centres, with a sufficient number of supplementary 
landing grounds, the purchase of machines, spares, and stores, the 
estalflishment of depots for petrol oil, &c., The upkeep expenses, includ- 
ing replacements, care of engines and machines, and salaries of pilots, 
mechanics, photographers, &c., would also be no small item, although 
once the system overcame prejudice and inspired sufficient confidence 
to insure a large volume of work, the rapidity with which maps could 
be produced would in all probability reduce their expense to a fraction 
of that involved by present methods. 
It might be noted, too, that forest country, especially in a hill dis- 
trict, is about the worst possible for pilot and machine in the event 
of engine-failure, and consequent forced landing. Unless a clear area 
were available, and the pilot at a sufficient height to enable him to reach 
it, the machine would almost certainly be wrecked, and the pilot very 
possibly killed. ; 
It would obviously be out of the question for a forest authority, with 
the comparatively limited funds at its disposal, to attempt itself to 
‘inaugurate any such project, but it might be expected gladly to avail 
itself of the opportunity to procure plans by so rapid a means: should 
the necessary machinery be set in motion and the plans be available at 
reasonable rates. : 
_ It is suggested that the encouragement of these up-to-date survey 
methods is chiefly a matter for Government enterprise, and certainly 
lies somewhat outside the province of a department which, while it finds 
plans and maps vital for the efficient conduct of its work, has not their 
production as its primary aim. I have, however, no wish to throw cold 
water on the scheme; on the contrary, I think the forest authorities 
should give sympathetic consideration to any practical suggestion as to 
co-operation with other Departments which, like themselves, could well 
utilize the results of any successful project along the lines under con- 
sideration. 
In conclusion, I might suggest that perhaps some arrangement to 
the desired end could be made with the military authorities. Flying 
has become so much a matter of practical politics that the maintenance 
of a considerable aerial equipment in Australia would appear inevitable. 
This would, in all likelihood, include the provision of many of the aero- 
dromes, landing-grounds, and depots necessary for photographic survey 
work, and there should also be no excessive difficulty in arranging for 
the military pilots to devote a part of their time to this end. Such an 
arrangement would seem likely to benefit both parties, as Departments 
or the general public wanting plans could procure them quickly and 
easily, whilst the payment for them would hhelp to reduce the cost of 
maintenance of the military aerial branch. 
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