Van Koolbergen only made a pretended effort to blow up the tunnel. He did furnish the evidence, however, which served to send Bopp and his associates to the penitentiary.
Even more sensational was the plot against the international bridge upon which the Grand Trunk Railway crosses the border between the United States and Canada at Vanceboro, Me.
Werner Horn was a German reserve lieutenant. Von Papen delivered to him a flat order to blow up the bridge and he gave him $700 for the purpose of perpetrating the outrage. Horn was partially successful. At his trial in Boston in June, 1917, he made the following confession:
"I admit and state that the facts set forth in the indictments as to the conveyance of explosives on certain passenger trains from New York to Boston and from Boston to Vanceboro, in the State of Maine, are true. I did, as therein alleged, receive an explosive and conveyed the same from the city of New York to Boston, thence by common carrier from Boston to Vanceboro, Maine. On or about the night of February 1, 1915, I took said explosive in a suitcase in which I was conveying it and carried the same across the bridge at Vanceboro to the Canadian side, and there, about 1.10 in the morning of February 2, 1915, I caused said explosive to be exploded near or against the abutments of the bridge on the Canadian side, with intent to destroy the abutment and cripple the bridge so that the same could not be used for the passage of trains."
Bribery of Congressmen was intended by Franz von Rintelen, operating directly in touch with the German Foreign Office in Berlin. Count von Bernstorff sent the following telegram to Berlin in connection with his plan:
I request authority to pay out up to $50,000 in order, as on former occasions, to influence Congress through the organization you know of, which can perhaps prevent war. I am beginning in the meantime to act accordingly. In the above circumstances, a public official German declaration in favor of Ireland is highly desirable, in order to gain the support of the Irish influence here.
That it was Rintelen's purpose to use large sums of money for the purpose of bribing Congressmen was stated positively by George Plochman, treasurer of the Transatlantic Trust Company, where Rintelen kept his deposits.
Rintelen was the main figure on this side of the water in the fantastic plot to have Mexico and Japan declare war upon the United States. During the trial of Rintelen in New York City in May, 1917, it was testified "that he came to the United States in order to embroil it with Mexico and Japan if necessary; that he was doing all he could and was going to do all he could to embroil this country with Mexico; that he believed that if the United States had a war with Mexico it would stop the shipment of ammunition to Europe; that he believed it would be only a matter of time until we were involved with Japan."
Rintelen also said that "General Huerta was going to return to Mexico and start a revolution there which would cause the United States to intervene and so make it impossible to ship munitions to Europe. Intervention," he said, "was one of his trump cards."
Mexico was the happy hunting-ground for pro-German plotters, and the German Ambassador in Mexico, Heinrich von Eckhardt, was the leader in all the intrigues. The culmination of Germany's effort against America on this continent came on January 19, 1917, when Dr. Alfred Zimmerman, head of the German Foreign Office, sent the following cable to Ambassador von Eckhardt: