. American engineer and railroad journal . I find another advanlaue accrues alsn from the use of thesevery thin, sliar|) edged hollow blades -viz , that there is nonppi-eciitlilc reshtanre to rotiilimi that does mil CDiitrihntf to lftiii(]efficl. A marked contrast lo this de^iral)l(! quality is presentedin the results iiiveii \\y flixilih lilided fans, eonstrucleil to vnriithtir pitch antomntically, being normally of roorHi- pilch (whenslilll, but decreasing llieir |)itcli when rotated, and furtherdecreasing it with increase of speed. Some expiriments 1made with fans of this description showed
. American engineer and railroad journal . I find another advanlaue accrues alsn from the use of thesevery thin, sliar|) edged hollow blades -viz , that there is nonppi-eciitlilc reshtanre to rotiilimi that does mil CDiitrihntf to lftiii(]efficl. A marked contrast lo this de^iral)l(! quality is presentedin the results iiiveii \\y flixilih lilided fans, eonstrucleil to vnriithtir pitch antomntically, being normally of roorHi- pilch (whenslilll, but decreasing llieir |)itcli when rotated, and furtherdecreasing it with increase of speed. Some expiriments 1made with fans of this description showed an unmistakableloss of power, as compared with the other type above de-scribe 1, due apparently to the energy absorbed in deHeclingthe elastic blailes ; which detieclion, with a giiien speed,causes a strain and resi-stancc, with no compensatinguseful effect. In 1888 W. Beeson patented, in the United States, thesingular soaring device sliowji in fig. 03. He had alreadypatented, in 1881, a. soaring apparatus consisting of two or. Fio more sets of adjustable superposed stretched on in-verted A frames, which he expected to raise into the airlike a kite, and then sail upon the wind, but he apparentlyabandoned this device in favor of the simpler foim shownin fig. 03, This consisted in a mainsail A and a tail or back-sail li,both of which were supported on a plate or board C, rang-ing fore and aft. This plate was convexed at its upperedge so that the sail A might extend over, forward anddownward to a cross-bar forming the front edge, and thusenclose a head pocket to catch the wind. A forked pen-dulum-bar, I, was ])ivoted to the plate C, and it supportedat its lower end a trapeze arrangement to carry the oper-ator, who by means of three light cords extending to hishand might alter the angle of incileni* of the mainsail .1,of the tail Ji, or of the rudder A*. The mainsail and tailbeing, moreover, connected by an adjustable bar, whichcaused the mainsail
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroadengineering
