It will have been noted that the last sight-line on Arcturus was marked by a barrow. Captain Henderson inspected it and found it much ruined by explorers, remains of a chamber inside being visible. In a subsequent visit, in which Captain Henderson was accompanied by Mr. Horton Bolitho, my wife and myself, we not only visited this barrow, but found that the whole hill had been honeycombed to such an extent by mining operations that it was very difficult to discriminate between “investigated” barrows and other heaps and holes, unless the barrow showed the remains of a chamber. Our examination was not limited to barrows. Captain Henderson had spent a long bleak day in examining and measuring the stones marked on the Ordnance Map, to which I had called his special attention. We went over part of the ground with him, and came to the conclusion that the whole question of the Cornish treatment of “ancient stones” would have to be gone into--an inquiry which Mr. Bolitho is now carrying on. It must be remembered that any stone or barrow used in the sight-lines we are now considering must have been put up nearly 4,000 years ago, so long ago, in fact, that many of the chief barrows have been reduced to the skeletons of their former selves, the enclosed stone chamber, built of mighty stones, alone remaining. Cromlechs and standing stones then formed important points in the landscape long before ecclesiastical divisions were thought of, or any attempt was made to indicate the boundaries of private property. We should expect then to find these ancient monuments freely made use of to mark what we now term “parish boundaries.” This is so. Four parishes have thus used one of the larger cromlechs, and it is more than probable that something beside the denunciation of the _cultus lapidum_, which we have seen at work in Brittany (p. 39), has been responsible for the many stone crosses in Cornwall. Of some of them near circles I have gathered the astronomical use, while now they “mark the bounds,” as do some of the stone rows in Dartmoor. I believe that in later times this practice of the Church was followed by those among whom the land was distributed, and this has gone on till at last there are many ancient stones trimmed on one side and bearing initials and so having a modern appearance. The astronomer, and even the archæologist, may regret this practice, but as the habit in Cornwall appears to be for anybody to use the nearest uncrossed and uninitialled stone for a wall or a pigsty, Mr. Bolitho’s inquiry may show that in some cases, at all events, it has been a blessing in disguise, for the stones are still there. In the case of a long chambered barrow, the top of which nearly touches the horizon, as seen from a circle near it, there is less danger of being misled.