The Moon's Influence on the Earth's Magnetism, An Orchid with Explosive Flowers

S. Chapman
1914 Scientific American  
beam-engine. Beams, "walking beams" as they are sometimes called, are usually broken by water in the cylinder or some other extraneouE. cause, but sometimes they fail gradually from old age, the signs of failure being the appearance of small cracks sometimes in the flanges, sometimes in the webs. A beam in northeast Lan cashire began to develop such cracks; they were pointed out to the owner of the engine, their import was explained to him, and he wah advised to replace the beam. After
more » ... attentively and in silence to the explanation, he got up, put on his hat, and said: "Mister, them cracks be nowt; I shan't put in no new beam. Why't has nowt to do but wag up and doon." Chief Assistant at the Royal Observa tory , Greenwich SCHUSTER has proved that the varying field which causes the ordinary daily changes in the magnetic ele ments is produced by electric currents flowing mainly above the earth's surface, and located in the rarefied upper strata of the atmosphere, perhaps where the Aurorm have their origin. The air is rendered elec trically conducting in these tenuous regions presumably by the ultra-violet radiation from the sun. The electro motive forces which impel the currents are supposed to be produced by the motions of the air, as indicated by the barometric variation, across the earth's permanent field of magnetic force. A not unreasonable value for the electric conductivity of the atmosphere was indicated by Schuster's calculations, based on his theory.
doi:10.1038/scientificamerican06061914-368supp fatcat:u2im3hsszjhrpjrs2dlackjgmi