 | William Emerson - 1769 - 370 sider
...great circle PED perpendicular to the plane of projection EFG. Let a plane PHG touch the fphere in P ; then fince the circle EPD is perpendicular both to...projection , therefore it is perpendicular to their interfedion GH. The angles made by circles are the . fame as thofe made by their tangents, therefore... | |
 | William Emerson - 1793 - 386 sider
...PED perpendicular to the plane of projection EFG. Let a plane PHG touch the fphere in P; then'fince the circle EPD is perpendicular both to this plane...projection, therefore it is perpendicular to their interfcction GH. The angles made by circles are the fame as thofe made by their tangents, therefore... | |
 | Thomas Simpson - 1810 - 168 sider
...PED, perpendicular to the plane of projection EFG ; let a plane PHG touch the sphere in P ; then since the circle EPD is perpendicular both to this plane and to the plane of projection, it is perpendicular to their common section GH. The angles made by circles are the same as those made... | |
 | James Mitchell - 1823 - 666 sider
...PED, perpendicular to the plane of projection EFG. Let a plane PHG touch the sphere in P ; then, since the circle EPD is perpendicular both to this plane and to the plane of projection, it is perpendicular to their intersection GH. But the angles made by circles are the same as those... | |
 | Peter Nicholson - 1825 - 1046 sider
...to the plane of projection EFG. Let a plane PHG touch the sphere in P ; then, since the circle EFD is perpendicular both to this plane and to the plane of projection, it is perpendicular to their intersection GH. But the angles made by circles are the same as those... | |
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Through the angular point P and the center C, draw the plane of a great circle PED perpendicular to the plane of projection EFG. Let a plane PHG touch the fphere in... 