424 
Proceedings of the Royal Society 
Height of bottom of leaf above floor, . . 43‘7 
,, lower stone of leaf, . . . 27-75 
,, junction of the stones above the floor, = 71/45 
Now, 142-4 x -494,or nat. tan.of Gfrand Gallery angle, = 7032 
F13 B.I. 
A line || to axis of Grand Gfallery, drawn from of Gfreat 
Step, passes 1/13 B. I. below centre of joint of leaf. 
P. 96 L. & W. This and the next calculation. 
Distance of south wall of Antechamber from ^ of Step = 229-6 B.I. 
229 6 x -494 (nat. tan. Gfrand Gallery ^l) - 113 # 42 ,, 
show that the same line produced, strikes the south wall of the 
Antechamber at a height of 113-42 B. I. from the floor. As the 
boss is to the west of the centre of the room, we turn to that side, 
and find that the height of the granite wainscot there., where it 
bears against the south wall, is 111-8 inches or 1*62 B. I. lower 
than the spot indicated. But, on examining the course of the axis* 
itself of the Grand Gallery when produced, the following calculation 
shows that it passes through the lower stone of the leaf at a distance 
of 0*8 inch below its centre on its northern side, and on being pro¬ 
duced strikes the south wall of the Antechamber at a height above 
the floor of 104-02 B. I., or just an inch above the height of the 
wainscot on the east side, which reaches an altitude of 103T B. I. 
Thus connecting the inch, the granite leaf, and the rest of the 
building in a manner that none but the original Designer could 
have introduced 
P. 96 L. & W. 
North side of leaf (omit boss) from north side of step = 134-3 B. I. 
Height of bottom of leaf above 1 -o 7 
floor, . . 
One-half height of lower stone, 13"9 
Height of centre of lower stone, 57'6 
(P. 99 L. & W.) 
But 134-3 x -494 = 66*24 
and axis of ascending) 
passage continued | 
through Grand Gal- y = 9-4 
lery is 9*4 B.I. below j 
of Stept J - ( Height at which axisofGrand 
= 56'8 — -j Gallery strikes lower stone on 
( north side, 
or (57-6 - 56-8) or 0 8 B. I. 
below centre of stone. 
* That is, axis of 1st ascending passage continued through Grand Gallery, 
f See next calculation. 
