He uses those of Ibn-Junis in his discussion of the obliquity of the ecliptic, and also in the case of the problems of the greater inequalities of Jupiter and Saturn.
These represent but a part, and indeed but a small part, of the services rendered by the Arabian astronomers, in the solution of the problem of the nature of the world.

Meanwhile, such was the benighted condition of Christendom, such its deplorable ignorance, that it cared nothing about the matter.

Its attention was engrossed by image-worship, transubstantiation, the merits of the saints, miracles, shrine-cures.
This indifference continued until the close of the fifteenth century.
Even then there was no scientific inducement.

The inciting motives were altogether of a different kind.

They originated in commercial rivalries, and the question of the shape of the earth was finally settled by three sailors, Columbus, De Gama, and, above all, by Ferdinand Magellan.
The trade of Eastern Asia has always been a source of immense wealth to the Western nations who in succession have obtained it.