the case of the aeroplane, against 48 hours in the case of the dirigible. This may be taken as a fair indication of their relative capacity, though of no quantitative value as a guide to what is to be expected under service conditions. The possibilities of the future are here rather in favour of the airship; there is an absolute limit both of range and duration where the aeroplane is concerned.
On the question of storage or housing the advantage of the aeroplane is overwhelming; the aeroplane, especially if furnished with folding wings, can be stowed away in any ordinary shed or barn, or may be anchored in the open without serious risk, whereas the "balloon hall" necessary for the safety of an airship is not only costly, but is an unmistakable landmark for hostile aircraft at 20 miles distance. Again, bad weather affects the storage of an aeroplane but little, whereas the housing or getting out of an airship in a strong wind is a difficult and risky business, even under the best of conditions. A large Zeppelin may sometimes call for the services of 300 men.
The foregoing by no means exhausts the grounds of comparison, but is sufficient for the present purpose. It is scarcely necessary to point out the very great disparity of weight, and, incidental thereto, carrying capacity, between the two classes of machine; the large German Zeppelins have a gross weight, taken from their displacement, of 22 tons (military) up to 35 tons (naval); of the aeroplanes in service, practically all the military machines are less than 1 ton "tare," and most types do not exceed 1 ton gross—i.e., with full complement, petrol, oil, etc.
If we were concerned with the primary function of the aeronautical arm alone, there appears to be no reason to doubt that both kinds of aircraft would have their place; the large air-ship has unquestionable
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