Lectures on Explosives; A Course of Lectures Prepared Especially as a Manual and Guide in the Laboratory of the U.S. Artillery School

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: sired effect more easily than the others. It may be considered that the fulminating mercury sets up a form of motion or vibration to which the other bodies are sensitive. Just as a vibrating body will induce corresponding vibrations in others, so the peculiar rate of motion, or wave of impulse, sent out by fulminating mercury, exerts a greater disturbing influence upon the molecules of certain bodies than that derived from other substances. An explosive molecule is unstable and very susceptible to external influences. Its atoms are in a nicely balanced state of equilibrium, which is, however, more readily overturned by one kind of blow than another. The explosive molecule takes up the wave of impulse of the fulminate, but the strain is too great, and its own balance is destroyed. In addition, the explosion proceeds very differently when brought about in this way than when caused by simple inflammation. When a mass of explosive is ignited by a flame, the action extends gradually through it; but if it is exploded by a blow, acting in the manner above described, it is plain that the explosion will be nearly instantaneous throughout, since the impulse will be transmitted through the mass with far greater rapidity than an inflammation proceeding from particle to particle. The explosive reaction will then proceed much more rapidly, and the explosive effect will be much sharper, that is, more violent. Combustion, Explosion, Detonation. These terms are used to express different phases of the same reaction, depending almost altogether upon the velocity of propagation of the explosive reaction. This may considered absolutely true with regard to the first two phenomena. In the case of combustion the reaction progresses very slowly and gradually, and can be controlled by mechanical m...