XVIII < ONTKNT*. 



.81. Second Process . . .67 



. 82. Third Process 68 



. 83. Fourth Process . . .68 



. 84. Position of the Derived Forms . 69 



. 85. Series . . . .69 



. 86. Limits . . . 70 



. 87. Fundamental Form . . .71 



1 Derivations from the Scalene Four-aided Pyramid. 



. 88. Derivation of more acute and more obtuse Pyramids, 



of similar bases with the Fundamental Form 72 



. 89. Ratio between the Derived and the Fundamental 



Form ... 73 



. 90. Series of Scalene Four-sided Pyramids, whose bases 



are similar to the base of the Fundamental Form 7-1 

 . 91. Limits of the Series of Scalene Four-sided Pyramids 77 

 . 92. Derivation of Scalene Four-sided Pyramids of 



dissimilar transverse Sections . 78 



. 93. The Ratio of the Diagonals of the Bases is de- 

 pendent on m . . 81 

 . 94. Ratio of the Derived and the Fundamental Form 82 

 . 95. Series of Derived Pyramids of a dissimilar trans- 

 verse Section with that of P. Other method 

 of deriving Pyramids of the same kind . 84 

 . 96. Subordinate Series . . 89 

 . 97. Horizontal Prisms . . .91 

 . 98. Series of Horizontal Prisms, and their limits. In- 

 clination of the Axis . .93 



2. Derivations front the Isosceles Four-sided Pyramid. 



. 99. Derivation of Homogeneous Forms . 97 



. 100. Ratio between the Derived and the Fundamen- 

 tal Form . . .98 

 .101. Series of Isosceles Four-sided Pyramids 99 

 . 102. Limits of the Series . .101 

 . 103. Derivation of Scalene Eight-sided Pyramids 102 

 .$ 104. The bases of the Scalene Four-sided Pyramids 



depend upon m . . 104 



