### ‘ι κίμε οι ςώόστερ -”ΐμτανγ ξώιτιξόρ

Ρεμ εμτοπΏσαλε ξώιτιξίρ στιρ σθμόηειρ τοποηεσΏερ.

### –εώιεςϋλεμα

 INTRODUCTION 1 REGULAR POLYHEDRONS 49 PYRAMIDS AND CONES 79 THE SPHERE 105
 APPENDIX TO SOLID GEOMETRY PAGE 157 INDEX 207 –μεθλατιξή διξαιΰλατα

### Ργλοωικό αποσπήσλατα

”εκΏδα 6 - If a line is perpendicular to one of two parallel lines, it is perpendicular to the other also.
”εκΏδα 45 - The sum of the face angles of any convex polyhedral angle is less than four right angles.
”εκΏδα 199 - COR. 2. The volume of a rectangular parallelopiped is equal to the product of its base by its altitude.
”εκΏδα 44 - The sum of any two face angles of a trihedral angle is greater than the third face angle.
”εκΏδα 65 - The volume of any parallelopiped is equal to the product of its base and altitude. Given any parallelopiped P with area of base b and altitude h.
”εκΏδα 33 - The acute angle which a line makes with its own projection on a plane is the least angle which it makes with any line in that plane. Given the line AB, cutting plane P at 0, A'B' the projection of AB on P, and XX' any other line in P, through 0.
”εκΏδα 33 - The projection of a straight line on a plane is a straight line in that plane.
”εκΏδα 105 - A sphere is a solid bounded by a surface all points of which are equally distant from a point within called the centre.
”εκΏδα 17 - Equal oblique lines from a point to a plane meet the plane at equal distances from the foot of the perpendicular...
”εκΏδα 6 - Two triangles are congruent if two angles and the included side of one are equal respectively to two angles and the included side of the other.