For that reason to arrest such men as Carl Heynen or Professor Hanneck is merely a precautionary measure. Whatever connection these men may have had with the German Government formerly, their work is now done, and their detention does not hinder the workings of the real spy system one iota. HOW THE SPY SYSTEM WORKS. It is difficult to distinguish between the work done in neutral countries by the secret diplomatic agent—the man who is engaged in fomenting disorders, such as I have described—and the spy, who is seeking military information which may be of future use. The two work together in that the secret agent reports to Berlin the names of inhabitants of the country concerned, who may be of use in securing information of military or naval value. It is well to remember, however, that the real spy always works alone. His connection with the government is known only to a very few officials, and is rarely or never suspected by the people who assist him in securing information. Here permit me to make a distinction between two classes of spies: the agents or directors of espionage, who know what they are doing; and the others, the small fry, who secure bits of information here and there and pass it on to their employers, the agents, often without realizing the real purpose of their actions. In the building of the spy system in America, Germans and German-Americans have been used. Business houses, such as banks and insurance companies, which have unusual opportunities of obtaining information about their clients—most of whom, in the case of German institutions in this country, are of German birth or descent—have been of service in bringing the directors of spy work into touch with people who will do the actual spying. The German secret service makes a point of having in its possession lists of people who are in a position to find out facts of greater or less importance about government officials. Housemaids, small tradesmen, and the like, can be of use in the compiling of data about men of importance, so that their personal habits, their financial status, their business and social relationships become a matter of record for future use. These facts are secured, usually by a little “jollying” rather than the payment of money, by the local agent—a person sometimes planted in garrison towns, state capitals, etc.—who is paid a comparatively small monthly sum for such work. This information is passed to a director of spies, who thereby discovers men who are in a position to supply him with valuable data and who determine whether or not they can be reached.