Popular science monthly . remove d and d r i \- e n into another nearbv section. Much of this work is carriet 1 on both at the surface . md be- n e a t h t h eground indrifts, duringthe wintermonths, thegravel removedbeing piled ingreat dumpsto await thesummer seasonof abundantflowing water. Theand Long, hollow tubes are driven into the ground in rowsand steam is forced through them for several hours Look Out! Perhaps the Man YoureTalking to Wears a has been issued:o William Heymann, ofIashington, D. C, on adevice which records ona graphophone drumhispered conversa-tions, wi
Popular science monthly . remove d and d r i \- e n into another nearbv section. Much of this work is carriet 1 on both at the surface . md be- n e a t h t h eground indrifts, duringthe wintermonths, thegravel removedbeing piled ingreat dumpsto await thesummer seasonof abundantflowing water. Theand Long, hollow tubes are driven into the ground in rowsand steam is forced through them for several hours Look Out! Perhaps the Man YoureTalking to Wears a has been issued:o William Heymann, ofIashington, D. C, on adevice which records ona graphophone drumhispered conversa-tions, without thespeaker beingaware of the receiver,which is of theusual detecta-phone t\pe, is tol)e worn beneaththe shirtfront,and the electricbatter\- and cyl-inder of the re-cording grapho-phone are to behooked to thewearers awound-up dock-spring ami theneedle of thegraphophonetraces the zig-receiver is worn beneath the shirtfront zags produced by the graphophone is hooked on the belt the SOUnd fi8<S VnpiiUir Science Montlih/ Recording
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectscience, bookyear1872
