By whom and for what purpose or purposes were the megalithic circles at Stennis, Callernish, Leys, Achnaclach, Crichie, Kennethmont, Midmar, Dyce, Kirkmichael, Deer, Kirkbean, Lochrutton, Torhouse, etc., etc., reared? What were the leading peculiarities in the religious creed, faith, and festivals of Broichan and the other Caledonian or Pictish Magi before the introduction of Christianity? When Coifi, the pagan high-priest of Edwin, the king of Northumbria and the Lothians, was converted to Christianity by Paulinus, in A.D. 627, he destroyed, according to Bede, the heathen idols, and set fire to the heathen temples and altars; but what was the structure of the pagan temples here in these days, that he could burn them,--while at the same time they were so uninclosed, that men on horseback could ride into them, as Coifi himself did after he had thrown in the desecrating spear? Was not our city named after this Northumbrian Bretwalda, "Edwin's-burgh?" Or was the Eiddyn of which Aneurin speaks before the time of Edwin, and the Dinas Eiddyn that was one of the chief seats of Llewddyn Lueddog (Lew or Loth), the grandfather of St. Kentigern or Mungo of Glasgow, really our own Dun Edin? Or if the Welsh term "Dinas" does not necessarily imply the high or elevated position of the place, was it Caer Eden (Cariden, or Blackness), at the eastern end of the Roman Wall, on the banks of the Forth? Did our venerable castle rock obtain the Welsh name of Din or Dun Monaidh, from its being "the fortress of the hill," and was its other Cymric appellation Agnedh, connected with its ever having been given as a marriage-portion (Agwedh)? Or did its old name of Maiden Castle, or Castrum Puellarum, not rather originate in its olden use as a female prison, or as a school, or a nunnery? And is it true, as asserted by Conchubhranus, that the Irish lady Saint, Darerca or Monnine, founded, late in the fifth century, seven churches (or nunneries?) in Scotland, on the hills of Dun Edin, Dumbarton, Stirling, Dunpelder, and Dundevenal, at Lanfortin near Dundee, and at Chilnacase in Galloway? When, and by whom, were the Round Towers of Abernethy, Brechin, and Eglishay built? Were there not in Scotland or its islands other such "_turres rotundae mira arte constructae_," to borrow the phrase of Hector Boece regarding the Brechin tower?