Gabb, Thomas: Finis pyramidis or Disquisitions concerning the antiquity and scientific end of the great pyramid of Giza, or ancient Memphis, in Egypt, and of the first standard of linear measure (Retford, 1806)

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and terminating in a point on the top of the axis, "shall
be so cut, as of the height there may be TV of it's own
expanse, (latitudtnis sua")

The first greatest expanse is equal to all the 8
parts, each 3| minutes, from the soffit of the abacus to
the bottom of the volute : aud 3-f multiplied by 8=26f
minutes, of which, T'Tis=2|• minutes ; the height, then,
of the rim, at the soffit of the abacus, is to be 22 mi-
nutes : then the next largest expanse is evidently com-
posed of the radius of the first quadraiit=13f minutes,
added to the radius of the third quadrant=10 minutes ;
the sum of these is 23χ minutes, of which rè is=1 4-|
minute ; the rim, therefore, at the junction of the limb
of the first quadrant, with the limb of the second
quadrant, is 144 minute : then, if the distance from the
thirteenth centre, on the circumference of the eye, to
the point of contraction of the rim under the soffit of
the abacus, is equal to the distance from the said cen-
tre to the point of contraction, at the junction of the
first, with the limb of the second quadrant, it will be
demonstrated, that centres placed at £ part of the |
circle of the eye, from the other 3 first centres, the radii
from them will properly and equally scribe all the se-
cond set of quadrants ; and the contraction of the rim,
will be every where exactly ,*¿ of the expanse of the
volute respectively, throughout the 3 circles of the eye.

Now, it is known the radius of the first quadrant
was=13,e8, and the thirteenth centre on the circumfer-
ence of the eye is distant from the soffit of the abacus
,s8 more, than the first distance taken from the top of
the eye ; consequently the thirteenth radius, before any
deduction is made for the breadth of the rim, must be
1344» and if this length of radius on this centre were to

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