I have stated in the Foreword that at the present time the submarine is a tremendous factor in the political and industrial economy of the world, and I believe that a treatment of the submarine which gives no consideration to it in this broader relationship to the life and welfare of humanity is altogether incomplete. In my opinion, just as the submarine is to-day a power to be reckoned with in the world--an agency the prodigious capacity for destruction of which we realize but too well--so is it to be in the future an instrument the influence of which upon the progress and safety of the nations of the earth will be well-nigh incalculable. Temporarily, it presents itself as a power for evil, as the weapon, the bludgeon, as it were, of either a misguided people or of an overbearing and power-thirsty aristocracy; permanently, I believe, it will prove to be destined to work for the highest good of humanity, and will serve the noblest and most intimate interests of men; for, as I have asserted above, the submarine has by no means been brought to its fullest measure of development. The limit of its capabilities has not been approached by modern ship constructors, even remotely. It will have a future; it has a destiny; it will serve mankind. There have been many criticisms and attacks directed at the submarine and against the designers of submarines within the past few years. These may be classified in general into two main categories: first, those which discredit the submarine on the basis of its mechanical limitations, and, secondly, those which assail the submarine on moral and humanitarian grounds and condemn the use of the weapon as piratical and murderous. For people who criticise the submarine on the grounds first stated I have little sympathy; they are those "who have eyes and see not, and having ears, hear not." They disavow the very testimony of the senses. I can, however, fully sympathize with those who attack the submarine on the latter basis; the events of the past three years may have borne this conviction upon them. Yet they also fail to realize that the submarine, in the end, will render great benefits and service to the world. They judge too much from the present and look too rarely into the future. By way of answering these criticisms I will be able to present the facts concerning the future of the submarine as they appear to me after years of thought and experimentation in this field. [Illustration: THE "ARGOSY AND ARGONAUT III" A house boat with submarine and access tube attached, built by the author in 1917, for pleasure and experimental purposes in making underwater explorations and investigation of sea coast waterbed formation, in locating beds of shellfish, wrecks, etc., and to demonstrate the practicability of their recovery. The house boat is 100 ft. overall, 20 ft. beam. The submarine can operate up to depths of 150 ft. by adding additional lengths of access tube.]