The Encyclopedia britannica; a dictionary of arts, sciences, and general literatureWith new maps, and original American articles by eminent writersWith American revisions and additions, bringing each volume up to date . e upper part of the tub^,and polar axis being omitted. Thefigures show the telescope directedto the pole, the hour circle being set e from the meridian. > The-^ ^ polar axis consists of a hollow , ,, ., . _ ., ^ ^ ,^ tm^ r . - FtQ. 11- — -1- .- ----Or. cone C (fig. 1 /) of cast, iron bolted to atollow cast-iron tube H, to the lower side of whichis attached a short steel axis
The Encyclopedia britannica; a dictionary of arts, sciences, and general literatureWith new maps, and original American articles by eminent writersWith American revisions and additions, bringing each volume up to date . e upper part of the tub^,and polar axis being omitted. Thefigures show the telescope directedto the pole, the hour circle being set e from the meridian. > The-^ ^ polar axis consists of a hollow , ,, ., . _ ., ^ ^ ,^ tm^ r . - FtQ. 11- — -1- .- ----Or. cone C (fig. 1 /) of cast, iron bolted to atollow cast-iron tube H, to the lower side of whichis attached a short steel axis carrying the driving sector EF andthe hour circle R, and terminating in the lower pivot of the polaraxis. This pivot a is terminated by a piece of chilledcast iron polished flat on its lower face, which face re-volves in contact with a piece of bell metal, Sat on itsupper and partly spherical on its lower side, bearing ina corresijondingly shaped annulus, formed to receive i;in the cast-iron block which is attached to thepier. This arrangement enables the bell-metalcushion to take its own position when the direc-tion of the polar axis is slightly changed in pro-cess of adjustment. The ptessnie of the pivot on. its bearings, in the direction at right angles to the polar axis, ii v^w,i,^a, lu i,,^ uiic<.iiuu A\. ri^ut angles lo me polarrelieved by the sector A, which is forced up by the screw dthrough laininje of steel The end pressure of a u ictingi|niD ir
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Keywords: ., bookcentury1800, bookdecade1890, bookidencyclopedia, bookyear1892
