Much of the recent progress has been, we may indeed say, entirely dependent upon the introduction of the methods of inquiry to which I refer. While this is generally recognised, it is often forgotten that a knowledge of even elementary astronomy may be of very great assistance to students of other branches of science; in other words, that astronomy is well able to pay her debt. Amongst those branches is obviously that which deals with man's first attempts to grasp the meaning and phenomena of the universe in which he found himself before any scientific methods were available to him; before he had any idea of the origins or the conditionings of the things around him. In the present volume I propose to give an account of some attempts I have been making in my leisure moments during the past three years to see whether any ideas could be obtained as to the early astronomical views of the Egyptians, from a study of their temples and the mythology connected with the various cults. How I came to take up this inquiry may be gathered from the following statement:-- It chanced that in March, 1890, during a brief holiday, I went to the Levant. I went with a good friend, who, one day when we were visiting the ruins of the Parthenon, and again when we found ourselves at the temple at Eleusis, lent me his pocket-compass. The curious direction in which the Parthenon was built, and the many changes of direction in the foundations at Eleusis revealed by the French excavations, were so very striking and suggestive that I thought it worth while to note the bearings so as to see whether there was any possible astronomical origin for the direction of the temple and the various changes in direction to which I have referred. What I had in my mind was the familiar statement that in England the eastern windows of churches face generally--if they are properly constructed--to the place of sun-rising on the festival of the patron saint; this is why, for instance, the churches of St. John the Baptist face very nearly north-east. This direction towards the sun-rising is the origin of the general use of the term _orientation_, which is applied just as frequently to other buildings the direction of which is towards the west or north or south. Now, if this should chance to be merely a survival from ancient times, it became of importance to find out the celestial bodies to which the ancient temples were directed. When I came home I endeavoured to ascertain whether this subject had been worked out: I am afraid I was a nuisance to many of my archæological friends, and I made as much inquiry as I could by looking into books. I found, both from my friends and from the books, that this question had not been discussed in relation to ancient temples, scarcely even with regard to churches outside England or Germany.