Schubert, Hermann, 1848-1911 · Chicago : Open Court Pub. Co. ; London : Kegan Paul, Trench, Truebner · leaf 101
ngles 1-2 and 2-5, 1-3 and 3-5, and 1-4 and 4-5 intersect at a point, which we will call 1-5. If now we cause the sides of the triangles which are opposite to these angles to intersect, it will be found that the points of intersection so obtained possess the peculiar property of lying all in one… … Fig. 36. dimensional space of ex- perience, in which the plane of the drawing lies, the proposition can be rendered almost self-evident. To begin with, imagine any five points in space which may be denoted by the numbers i, 2, 3, 4, 5 ; then imagine all the possible ten straight lines of junction…
