From the point of view which now concerns us, it may be said that the new discoveries might be arranged into three different groups. First of all, the land had been found full of temples, vast and majestic beyond imagination; among these the temples at Karnak were supreme, but there were others on a par with them in points of architectural detail. But besides these, then as now, above ground and inviting inspection, there were many others which were then--as undoubtedly many are still--more or less buried in the sand; some of these have since been unearthed to reveal the striking features of their structure. I shall show subsequently that, on the evidence of the ancient Egyptians themselves, these temples were constructed in strict relation to stars; they, then, like the pyramids, must be taken as indicating astronomical knowledge. If we deal with the general external appearance of the temples, they may be arranged architecturally into two main groups. Edfû is the most perfect example of the first group, characterised by having a pylon consisting of two massive structures right and left of the entrance, which are somewhat like the two towers that one sometimes sees on the west front of our English cathedrals. In Denderah we have an example of the second group, in which the massive pylon is omitted. In these the front is entirely changed; instead of the pylon we have now an open front to the temple with columns--the Greek form of temple is approached. [Illustration: GREAT COURT OF HEAVEN, AT THE ENTRANCE TO THE HATHOR TEMPLE AT DENDERAH.] Associated with many of the temples, frequently but not universally in close proximity to the propylon, were obelisks, often of gigantic proportions, exceeding one hundred feet in height and many hundreds of tons in weight, which it has since been discovered were hewn out of the syenite quarry at Aswân, and floated down the river to the various places where they were to be erected. It is not necessary to go to Egypt to see these wonderful monoliths, for they have been carried away from their original temple sites at Thebes and Heliopolis to adorn more modern cities in the Western world. London, Paris, Rome, and Constantinople are thus embellished. It is obvious to anyone acquainted with astronomical history and methods, that some of these structures, at all events, may have served as gnomons. [Illustration: TEMPLE GATE WITH PROPYLON AND OBELISKS.] Sometimes these temples, instead of being entirely constructed of stone on a level surface, were either entirely or partly rock-hewn. Of the former class, the temple of Abu Simbel is the most striking example; of the latter, the temple of Dêr el-Bahari at Thebes. [Illustration: HATHOR TEMPLE OF DÊR EL-BAHARI. (_As restored by M. Brune._)]