Submarine and Anti-submarine

“It is probable that a good deal of the information contained in this book will be new to the public; for it has been collected under favour of exceptional circumstances. But the reader will gain little if he cannot contribute something on his side—if he cannot share with the writer certain fundamental beliefs. The first of these is that every nation has a spirit of its own—a spirit which is the mainspring of national action. It is more than a mechanical spring; for it not only supplies a motive force, but determines the moral character of the action which results.”