Chemistry and Physics. 161 



and the crucible allowed to cool gradually through the night. 

 The button, weighing about six ounces after removing the slag, 

 was found to be covered with small, very brilliant crystalline 

 faces. Pieces of the alloy were then broken up, and digested for 

 several days, in hot hydrochloric acid. The crystals unaltered 

 and but very slightly dimmed, remained separated from the mass 

 of the alloy. Except on the one face, the crystals were not bril- 

 liant enough to be measured by the reflecting goniometer. Such 

 as could be obtained appeared to be like trigonal prisms, and 

 were inferred to belong to the triclinic system. Their hardness 

 was above 7, so that they easily scratched quartz, and they were 

 quite brittle. Specific gravity, 15-^ to 16. Color, steel gray. 

 Analysis showed 99^ to 98 per cent tungsten, with trace to 2 per 

 cent iron. Carbon was probably present but was not determined. 

 After pulverizing, and heating for three days with concentrated 

 hydrochloric acid, the tungsten was not acted on, and the hydro- 

 chloric acid contained no tungstic acid. An alloy of tungsten with 

 nickel shows even more tendency to form the crystals of tungsten. 

 University of Pennsylvania. 



7. Influence of Solar radiation on Electrical phenomena in 

 the Atmosphere of the Earth. — Sv. Arrhenitts concludes, from a 

 series -of investigations, that the air irradiated by ultra violet 

 light conducts like an electrolyte. On Peltier's hypothesis that 

 the earth is charged negatively Arrhenius endeavors to explain 

 the, electrical phenomena of the earth as the result of solar radi- 

 ation. The solid and liquid particles suspended in the air carry 

 the electricity which they obtain from the earth by conduction 

 when the air becomes a conductor under the influence of the sun's 

 rays. Feeble electrical currents exist in the air as a result of this 

 carrying process. On cloudy days the fall of potential is much 

 lower than on bright days. Hail is for the most part negative, 

 while snow is occasionally positive because it occurs at periods 

 when the sun's action is the weakest. These facts the author 

 thinks support his theory. The positive fall of potential noticed 

 in morning fogs he believes is due to the sun not having acted on 

 the fog. A table of Quetelet is referred to which shows, from 

 many years' observations, that the monthly mean of the strength 

 of atmospheric electricity is the less the greater the monthly 

 mean of the solar radiations measured by the actinometer. 

 Thunder storms result from the effects of solar radiation, and are 

 most frequent in hot countries, in the summer, and in the after- 

 noons. The lagging of the maximum occurrence of thunder- 

 storms behind the maximum of solar radiation the author 

 attributes to the time required for the charge and the coalescence 

 of individual drops. Cyclonic storms, occurring at night and in 

 winter, are supposed to be brought from southern regions. The 

 yearly and daily periods of atmospheric electricity are in accord- 

 ance with this theory. Since the greater part of the active solar 

 radiation is absorbed in the upper regions, these must conduct 

 better than the lower layers of air. Since these upper layers of 

 air are moving strongly from west to east round the earth, a con- 

 ductor would be obtained under the influence of the sun's rays 



