THE JETS OF BLUE A chemist friend of mine once invented a process of converting nitro-benzole into tri-nitro-benzole by a very quick and labor-saving method, which consisted in mixing the nitro-benzole with nitric acid, confining the mixture in a large, strong, steel cylinder, then gradually heating the cylinder until the required pressure should be produced, which was expected to effect the desired reaction. Accordingly, five hundred pounds of nitro-benzole was mixed with the necessary quantity of nitric acid of the requisite strength, and the heating process was begun. While anxiously watching this infernal machine, my friend saw a peculiar blue flame emerge from the seam around the head. Being of an alert nature, and able to take a hint without being kicked by an elephant, he withdrew from the vicinity of that cylinder. He did not merely sidle away from the perilous place--he fairly flew with an alacrity born of desperation. He had barely emerged from the laboratory when there was a terrific explosion that leveled the building, and formed an enormous crater in the earth where he had stood, the concussion knocking him senseless. And, today, he still swears, with solemn earnestness, that a freight car could have been buried in the hole that was blown in the ground when his pet project went off. This experience so impressed him that he concluded that explosive compounds possess properties which place them in a class by themselves, and that it is a good class to avoid. THE WISDOM OF RETREAT During the experiments with Maximite at Sandy Hook, previous to its purchase and adoption by the United States Government, I was loading some shell in a small house, near where a ten-inch gun was being fired. About a year or so before, when a ten-inch gun of this particular make was being tested at Sandy Hook, the breech block blew out, went through the bomb-proof, and killed several officers and men. Having completed my work, I started up the railroad track in the direction of the steamboat landing, to return home, when there came the ring of the bell for another discharge of the cannon. As the breech of the gun was pointing in my direction, I recalled the above fatality; but I reasoned with myself that, as a large number of tests had since been made with these guns, and as the defect in the breech mechanism was supposed to have been corrected, the chance of the breech blowing out at this particular discharge and coming my way was infinitely small. Nevertheless, I thought, it is exactly on such occasions that the unexpected does happen. So I ran for all I was worth up the track and off at one side. Then I heard the report of the gun, and looking around, saw that sure enough the breech block had blown out, and saw it pass through a building in its path. I saw it strike the track over which I had been walking, cut a rail off, saw it strike the old stone fort beyond me, and ricochet high into the air.