In this connection, I cannot do better than quote an instructive passage from Paul Lenoir's masterly book on "The German Spy System in France," one of the most complete and fascinating exposures of German machinations that has ever been written, and a veritable mine of information on German aims and methods. Lenoir relates how, on one occasion, he had a long conversation with a very distinguished member of the German spy administration who had expressed the wish to meet him. In the course of their conversation, the German said:-- "Ah! If only you knew how many of your politicians who shout and declaim in France demanding the suppression of _your_ Secret Service funds--if you only knew how many of those men are drawing thumping good salaries out of _our_ Secret Service funds; if only you knew what proportion of their election expenses is paid by us every four years!" I do not suppose for a moment that we have in England anything of this kind; the class of men who secure election to the House of Commons is no doubt above temptation. I, however, mention this instance, revealed be it remembered by a Frenchman working hard in his country's cause, to show how very far the German espionage bureau is prepared to go to seduce men from their natural allegiance, and convert them into the most dangerous enemies of their country. And, with regret I confess it, we have to face the fact that even in our own services there are some whose honour is not proof against the lavish stream of German gold. How to detect and defeat them is indeed a difficult problem; all we can say is that in this, as in other matters, eternal vigilance is the price of liberty. But at least we can say that when they are caught these men ought to be made to pay a terrible price for their treachery, as an example and a deterrent to others. There must be no illegal sentences of death, as in the Ahlers case. There must be no paltering with this blackest of crimes, and no concession to the sentimentalists of the cocoa-Press. In conclusion, I appeal to my readers to believe that I do feel, after many years' study of this subject, that in German espionage lies one of the greatest dangers our beloved country has to face. I earnestly appeal to them to do all in their power to assist in forming a vigorous public opinion, that shall insist that, at whatever cost, this canker in our public life shall be rooted out. We must--and we can, if we devote our attention to it--make an end to the spy in our midst, and make it impossible that our hospitality shall be abused by those who are plotting our downfall. To do this a strong and healthy public opinion, which shall drive supine officials to determined action, is the first and greatest requisite. Without that--and it is the purpose of this book to assist in rousing it--we shall drift back into the old rut of contemptuous and incredulous neglect, and it is more than probable that our last state will be worse than our first.