ABOUT THE ATMOSPHERE AND ITS PHENOMENA. 721 



The earth is evei* heated in part, ever cooling in part. The Sun is con- 

 stantly shining on some portion of the globe, while another portion is con- 

 tinually in shadow. That portion on which the Sun shines at midday is 

 warmer than that portion covered by mignight darkness — sometimes not less 

 than sixty degrees difference. By the well known law of thermal electri- 

 city currents must be excited where the surface is heated and flow to where 

 it is cooler — and thus we have currents always flowing from east to west — 

 from where it is day to where it is night — for to the Sun the west is night. 

 And by this current ever in flow, the earth becomes a magnet. This must 

 be, but how far the magnetic ray of the Sun itself assists, is unknown — we 

 only do know that the violet ray of the spectrum will render a needle 

 magnetic. 



Then again, constant parallel currents of electricity tend to converge, 

 and thus produce intense action, and again they tend to produce secondary 

 currents, and so on successively. By this method lateral currents are pro- 

 duced in or over the earth ^ as discovered by Faraday. These currents 

 sometimes become so intense as to produce what Humboldt calls magnetic 

 storms, from which comes the Aurora — so powerful at times that the tele- 

 graph can be worked without the aid of batteries. 



All currents of electricity passing through the air, tend to displace it, 

 and to create currents in it. Here are the inducing causes of the winds, 

 varying according to electrical activity, from the breeze that gratifies to 

 the tornado that is carried forward with such amazing velocity and such 

 terrible power. That it flows from the earth to the air conducted by the 

 same properties of matter, can be even seen at times by the naked eye — 

 from trees, from mountains and every object that elevates itself above the 

 common level of the mass of the earth — as well as on the sea from the masts 

 of ships. 



The discoveries of Meissner and Faraday, as to the magnetization of 

 oxygen, leave no further doubt that evaporation is to a great extent an 

 electric process, aided by heat, but acting independent of it. Dr. Kane 

 tells of thaws in the arctic regions during the long polar nights, when no 

 ray of San had visited them for weeks. And Captain Hall, on the farthest 

 point ever reached by explorer toward the pole, was gladdened by the far 

 northern horizon banked with nimbus clouds. This vapor when evaporated 

 is combined with the oxygen and electricity, and exists by that force in the 

 atmosphere. This acted upon, by static or inductive forces, perhaps, con- 

 denses, and clouds are the result. It takes place, we see, as readily in the 

 depths of the arctic night as in the heated atmosphere of the tropical day. 

 And the artic storm, which by this vaunted law, should be the result of 

 heat, by its icy breath destroys even lichen life and howls in those awful 

 solitudes, amid crashing icebergs and the groaning ice fields with a power 

 that surpasses the storm revels of the tropics. 



Dynamically, the heat of the Sun is incompetent to this task even under 

 the most favorable conditions. I must return to this theory once more, to 



