When you want to understand an old meaningless custom or belief, found in the middle of civilisation, you try to discover the belief or custom in some region where it possesses intelligible life. Then you may reckon that, where you now find it without meaning, it once meant what it now does where it is full of vitality, or meant something analogous. The place where the concentric circles and other markings have a living and potent signification I discovered by pure accident. I had been reading the proofs of Messrs. Spencer and Gillen's valuable book on the 'Native Tribes of Central Australia' (Macmillan). There I had noted plenty of facts about the native churinga, or 'sacred things,' flat oval pieces of wood or stone, covered with concentric circles, cups, and other decorations, which are read, or deciphered, as records of the myths and legendary history of the native race. These churinga are of various sizes, down to a foot or less in length. I did not think of them in connection with our cups, circles, and so forth on our boulders and standing stones. But a friend chanced to come into my study, who began to tell me about the singular old site, Dumbuck, discovered by Mr. W. A. Donnelly (July 1898), under high-tide mark in the Clyde estuary, near Dumbarton. 'The odd thing,' said my friend, 'is that they have found small portable stones, amulets marked in the same way as the cup and ring marked rocks,' and he began to sketch a diagram. 'Why, that's a churinga,' said I, 'a Central Australian churinga,' enlightened by Messrs. Spencer and Gillen. My friend, after being informed as to churinga, told me that other examples had been dug up, also by Mr. Donnelly, in an ancient fort near the other site, at a place called Dunbuie. Here, then, I had things very like churinga, and of the same markings as our boulders, kists, and so on, in two Scottish sites, where I understand neither pottery nor metal has yet been detected. Next, I found that the marks which the Australians engrave on their small churinga, they also _paint_ on boulders, rock-walls, and other fixtures in the landscape, on sacred ground, tabooed to women. The startling analogy between Australian and old Scottish markings _saute aux yeux._