The daily morning journal and courier., 1900-02-08
WHAT CAUSES THUNDER?
Theory Suggested for What is Yet ar
 Unexplained Phenomenon.

Theory Suggested for What is Yet ar
 Unexplained Phenomenon
 What is the cause of thunder, mean
 ing the cause of the noise? We do not
 know. The thunder, we. know, is a re- i suit of the phenomenon we call light
 ming" but just what it is has not been
 as yet adequately determined. The
 electric discharge produces a variety of
 effects, physiological, luminous, caloric.
 magnetic, mechanical and chemical,
 whose characteristics are more or less
 recognized. It is fair to presume that
 we must hunt for the cause of the noise | in the calorific, mechanical, or chemical attributes.
 | Most of the authorities in definition say thunder is the noise immediately following flash of lightning, and is due to the disturbance of the air caused
 along it's, path by the discharge, and they let it go at that.
 It may be that the real explanation will be found partly in each of the calo- rife, mechanical, and chemical actions. A mere disturbance of the air is hard ly an adequate reason. We have too little evidence to go upon The heating effects, so called, may have some bear ing. We know the spark will inhame ether( alcohol, and some of the hydro carbon gases; yet it does not ignite gun powder, except by the help of a wet string which becomes heated A Ley den jar charged and discharged several times in rapid succession becomes heat ed All solid conductors become heat ed by it. But does air? Mechanical effects are numerous and usually dis aetrous to any solid body not good conductor. We are shown by Kinners- ley'e thermometer that some effect is produced on body of water, but it is asserted not to be due to any increase of temperature in the air.
 The chemical, effects are most varied Priestly found reduction of volume in moist air by passage of the spark (which may be significantly and that the air became acid Cavendish found this was due to the formation of nitric acid by the chemical action of the discharge Compound gases are readily decom- posed but air is not a compound gas; it is merely a mixture of oxygen and nitrogen, and neither of its constituents is conbustible. One assists combustion of other bodies, while the other bodies of other bodies. while the other is inert in that sense.
 But we may get some light on the subject yet from the indefatigable army of electrical investigators. Possibly the researches in the liquefaction of gases may help out. Tn a recent paper on the subject it is stated that ozone liquefies at atmospheric pressure at a tempera- ture of 1854 degrees Fahrenheit and that is easily exploded Now, it is well known that the electric discharge pro- duces this so-called allopatric oxygen
 in great abundance. According to Priestly the electric discharge effects reduction of volume in moist air, which would indicate ordinarily fall of tenn perature. Moist air is the usual atmOs- pheric condition during lightningflashes. Possibly the stream of innumerable sparks in stroke of lightning produces a cumulative or intensive effect, first lowering the temperature, then forming ozone, then causing its liquefaction, and finally its explosion, or perhaps de- tonation. which expresses more accu- rately the terrifying crash following or accompanying a lightning stroke near at hand, This is mere speculation, and I give it for what it is worth. Electric al Review