Social environment and moral progress / by Alfred Russel Wallace.
- Alfred Russel Wallace
- Date:
- 1913
Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Credit: Social environment and moral progress / by Alfred Russel Wallace. Source: Wellcome Collection.
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![IV] Permanence of High Intellect dropped so as to obtain the exact line of the meridian on the surface, and after¬ wards on each successive step of the pyramid as it was built up. While the building went on the sloping tunnel was continued backwards to its northern face ; and a tunnel ascending to the south was formed of the same size and making the same angle with the horizon. This had puzzled all previous explorers of the pyra¬ mid till Mr. Proctor showed that, by stopping up the downward passage at the angle and filling the hollow with water the pole star could be observed by reflexion and thus ^ive the exact direction of the meridian on the upper surface of the pyramid with extreme accuracy, as it was built up slowly year by year. But at a distance of 127 feet a new feature appears. The ascending tunnel is changed into what is called the Great Gallery, which, while continuing exactly the same floor line as the tunnel, is sud¬ denly raised to a height of 28 feet, with a width of 7 feet on the floor and 3J feet at the top. Along each side there is a ledge or seat, 20 inches broad and 21 inches high. The sides do not slope in¬ wards, but are formed of seven courses of 21](https://iiif.wellcomecollection.org/image/b18022121_0034.JP2/full/800%2C/0/default.jpg)
