The subject I haveto talk about this evening is one on which many previous papers have been read before this Society, so I am afraid I must ask you not to expect much original material from me. Practically the whole of the material I have gathered together is the result of practical experience, and from this point of view I hope it will prove interesting.

During recent years considerable development has been done and good progress made with both the design and operation of big flying boats.Also, the Schneider Cup races have caused a considerable amount of research work to be done on the development of twin float seaplanes, particularly with regard to taking off the water at very high speeds and also to the air resistance of the floats.

In the last year we have seen the advent of the Dornier Do.X the largest flying boat yet constructed, whose total flying weight approximates to 50 tons.