. Report of the fifty-fourth meeting of the British Association for the Advancement of Science [microform] : held at Montreal in August and September 1884. Congresses and conventions; Science; Congrès et conférences; Sciences. ill ^ ^ 1*1 -:t 656 REPORTâ1884. from Madras on the Bay of Bengal to Bombay on the Arabian Sea will pive nn average maxium difterence on quiet days of 7 volts ; between IJellavy and Beliraiun two inland statioTis east and west, 200 miles, an average of 2 or 2h volts ; betwop Belgaum and Vingurla, a station inland and one on the sea coast, seventy miles, a average of 2'
. Report of the fifty-fourth meeting of the British Association for the Advancement of Science [microform] : held at Montreal in August and September 1884. Congresses and conventions; Science; Congrès et conférences; Sciences. ill ^ ^ 1*1 -:t 656 REPORTâ1884. from Madras on the Bay of Bengal to Bombay on the Arabian Sea will pive nn average maxium difterence on quiet days of 7 volts ; between IJellavy and Beliraiun two inland statioTis east and west, 200 miles, an average of 2 or 2h volts ; betwop Belgaum and Vingurla, a station inland and one on the sea coast, seventy miles, a average of 2'.'> volts. l'er!iaps 100 or ] oO volts i ' ' ' ' obtainable at tlH> widest limits on the earth's s always been possible to measure the potential * masrnotic storms,' but -JO volts per 200 miles is i. average of 2'.'5 volts. Perhaps 100 or loO volts might be expected as the maxium obtainable at tlH> widest limits on the earth's surface on quiet days. It has not difference occurring in SD-callcd â magnetic storms,' l)ut ^JO volts per iiOO miles is not uncommon. As recent years have tauglit with what minute currents speech and telegraphic symbols can be transmitted over long distances, the author suggests that thi' time may be coming when these earth currents shall be made of service for such purposes, and telegraphy shall in general benefit. It is found on disturbed days that actual reversals of the earth's currents take place in a few minutes; but that, certainly within a range of 900 miles, tiiesc reversals all agree on ditferent lines; that is, all places east arc positive or negative, at the same time, and places west of tiie opp;.bite sign simultaneously ; a large aveii' is affected at the same time and in the same way. Great throbs art felt, which increase or decrease the currents in all lines together like the beating of the pulses â¢of the body. Seeing' tiiat during tlie passage of sunspots, the obscured portion of the earth's surface is said to cease to
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1885
