. Appleton's dictionary of machines, mechanics, engine-work, and engineering. e position of the eye. Two of the principal properties of this projection are the following: 1. The projection of an\ circle onthe sphere which does not pass through the eye is a circle; ami circles whoso planes pass through theeye are projected into straight lines. 2. The angle made on the surface of the sphere by two circleswhich cut each other, and the angle made by (heir projections, is equal. 3. Gnomonic or central projection.—In this projection the eye is situated at the centre of the sphere,and the plane of pr
. Appleton's dictionary of machines, mechanics, engine-work, and engineering. e position of the eye. Two of the principal properties of this projection are the following: 1. The projection of an\ circle onthe sphere which does not pass through the eye is a circle; ami circles whoso planes pass through theeye are projected into straight lines. 2. The angle made on the surface of the sphere by two circleswhich cut each other, and the angle made by (heir projections, is equal. 3. Gnomonic or central projection.—In this projection the eye is situated at the centre of the sphere,and the plane of projection is a plane which touches the sphere at any point assumed at pleasure. The 526 PROVING MACHINE, HYDROSTATIC. point of contact is called the principal point; and the projections of all other points on the sphere areat the extremities of the tangents of the arcs intercepted between them and the principal point. Asthe tangents increase very rapidly when the arcs exceed 45°, and at 90° become infinite, the centralprojection cannot be adopted for a whole
Size: 966px × 2588px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectmechanicalengineering, bookyear1861
