But this was only a trial spin, so to speak. The following week the two practical jokers were at the Hippodrome, Portsmouth, where they shared a dressing-room with Harry Claff, known as the “White Knight.” Harry had not, as it happened, heard of the Sheffield incident, but the reputation of the Brothers Egbert in the matter of practical joking was, of course, well known to him, so that he was on his guard.
The brothers tried hard to get him away from their dressing-room after rehearsing together on the Monday, so that they could put some of the explosive stuff on his seat, his grease paints, his make-up box--anywhere, in short, where he would be sure to handle it or come in contact with it. But try as they would, they could not succeed. Harry stuck to them too tightly.
At length the three of them left the theatre to go to their respective diggings. The brothers saw Harry to his. Then Seth Egbert slipped hurriedly back to the dressing-room, and started smearing the stuff all over Claff’s various belongings. Now every theatrical dressing-room is provided with a mirror, and just as Seth had finished baiting his trap he happened to glance up into this mirror, and there, clearly reflected, was the face of Harry Claff, an amused grin on his face. Suspecting that the brothers were up to something, he had followed Seth back to the theatre, and caught him in the act.
I had the curiosity to inquire of the brothers how they made the stuff. Here is their formula; but if any of my readers contemplate making any of it, with a view to playing tricks on anybody, I warn them to be very, very careful, as the compound is exceedingly dangerous, being one of the most powerful explosives known, and used extensively in the late war.
You take sixpennyworth of flaked iodine and one pennyworth of 88 ammonia, together with a sheet of filter paper. Put a small piece of iodine on the filter paper held over a tin can, and pour over it enough ammonia to dissolve it into a paste. This, smeared while wet on any hard substance, such as the handle of a door, for instance, will explode--when dry--with quite a violent report directly anyone touches it. But no more than the tiniest piece, about the size of a pin’s head, must be used.