COSMIC PHILOSOPHY 



drum's investigation of the relations between 

 sun-spots and rainfall. And whatever may be 

 the final explanation of the phenomena of sun- 

 spots, there can be little doubt that the perio- 

 dicity of these phenomena is conditioned by the 

 positions of the various planets, and especially 

 of the giants Jupiter and Saturn. But these in- 

 terrelations, though they may be much more 

 important than is as yet suspected, need not 

 now detain us. Such further effects as may be 

 wrought upon the earth by polarized light sent 

 from the other planets, and by radiance from 

 remote stellar systems, may be left out of the 

 account. Nor need we do more than allude to 

 the moon's gravitative force as the chief cause 

 of the oceanic tides, with their resultant geolo- 

 gic phenomena. Passing over all these circum- 

 stances, we come to the still unexpended energy 

 represented by the earth's internal heat, con- 

 cerning which we need only say that it is the 

 cause of the geologic phenomena classed as igne- 

 ous. Volcanic eruptions, earthquake shocks, 

 elevations and subsidences of continents and 

 ocean - floors, metamorphoses of sedimentary 

 rocks, boiling springs, fractures of strata, and 

 formations of metallic veins, are the various 

 manifestations of this form of terrestrial energy. 

 But all these grand phenomena must be re- 

 garded as immeasurably inferior in variety and 

 importance to those which are due to the trans- 

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