of Edinburgh, Session 1869-70. 
165 
Independent Methods of Constructing the Great Pyramid Externally. 
1st. Grive a horizontal line. Bisect it, erect perpendiculars at 
both ends and also from the centre, from one of the ends throw up 
the unit angle with the vertical, and through the point where the 
angle cuts the opposite perpendicular draw a horizontal line, an 
oblong will thus be formed, the diagonal of which is the unit 
angle, join the top of the central perpendicular with the lower 
corners of the oblong, and the Pyramid is complete. 
2d. Gi-iven a vertical line, the radius of a circle, at right angles, 
through the centre of circle, draw a horizontal line, bisect the 
vertical line, and throw down the unit angle with the vertical from 
both sides of the vertical at its bisection, through the points where 
these cut the horizontal line, join the extreme end of the radius, 
and the Pyramid is complete. 
The Diagrams submitted to the Society were as follow:-— 
Diagram No. 1. — Construction of the Grreat Pyramid in its ex- 
ternal angles, its chambers and passages by the unit angle, and 
one-tenth of the base, on a given horizontal line. 
Diagram No. 2, one-sixteenth of the full size. — Sections of the 
King’s Chamber, in its length, and also in its breadth, showing- 
how it is regulated by the unit angle, &c. 
Diagram No. 3, one-half of the full size. — Sections of the 
granite coffer in its length, and also in its breadth, showing how it 
is regulated by the unit angle and conserves the Pyramid facial 
angle. 
Coffer unit block , in further illustration of Diagram No. 3. 
Diagram No. 4, one-sixteenth of the full size. — Section of the 
King’s Chamber in its breadth, the ante-chamber, great step, and 
south end of grand gallery, showing that the space between the 
King’s Chamber and ante-chamber, the form of the ante-chamber 
itself, and the distance to the great step, are all regulated by the 
unit angle; showing also the references between a portion of the 
VOL. VII. y 
