The month of July was a holocaust. A tank of phenol exploded in New York, the benzol plant of the Semet Solvay Company was destroyed at Solvay, N. Y.; on the 7th serious explosions occurred at the du Pont plant at Pompton Lakes and at the Philadelphia benzol plant of Harrison Brothers (the latter causing $500,000 damage); on the 16th five employees were killed in an explosion and fire at the Ætna plant at Sinnemahoning, Pa., three days later there was another at the du Pont plant in Wilmington; on the 25th a munitions train on the Pennsylvania line was wrecked at Metuchen, N. J.; on the 28th the du Pont works at Wilmington suffered again; and the month came to a fitting close with the destruction of a glaze mill in the American Powder Company at Acton, Mass., on the 29th. (The British army in Mesopotamia had just entered Kut-el-Amara at this time, and far to the northward Germany was prosecuting a successful campaign to force a Russian retirement from Poland.) Each incident raised havoc in its immediate vicinity. Each represents a carefully worked-out plan involving a group of destroying agents. There is not space here to describe the plots in detail, nor to picture the horror of their results. But the affidavit of Johannes Hendrikus Van Koolbergen, dated San Francisco, August 27, 1915, may serve to show typical methods of operation, as well as to provide a story more than usually melodramatic. Van Koolbergen was a Hollander by birth, and a British subject by naturalization. In April, 1915, he met in the Heidelberg Café, in San Francisco, a man named Wilhelm von Brincken, who lived at 303 Piccadilly Apartments, and who asked Van Koolbergen to call on him there. The latter, however, was leaving for Canada, and it was not until some five weeks later that he returned and found that in his absence von Brincken had twice telephoned him to pursue the acquaintance. Van Koolbergen called. Von Brincken explained that he was a German army officer, on secret service, and employed directly by Franz Bopp, the German consul in San Francisco. His visitor's identity and personality was apparently well known to him, for he offered Van Koolbergen $1,000 for the use of his passport into Canada, "to visit a friend, to assist him in some business matters." Van Koolbergen refused to rent his passport, but volunteered to go himself on any mission. This offer was discussed at a later meeting at the consulate with Herr Bopp, and accepted, after, as Koolbergen said, "I became suspicious, and upon different questions being asked me ... I became very pro-German in the expression of my sentiments."