Hither came the "dusky barge" that was to bear Arthur away to the isles of the blessed. This is very pretty; the lake, the black serpentine rocks agree well enough, but how was the fairy barge to get over the pebble ridge? Mr. Rogers had not then cut the culvert. No doubt it was brimming, but it must have been risky over the bar. I do not believe a word of it. Arthur never was down there. The reputed site of the battle is at Slaughter Bridge, near Camelford. But before we settle where the battle was fought, we must fix Arthur himself, and he is slippery (historically) as an eel. What makes the Lizard district interesting is in the first place the serpentine rock that forms it, and then the plants which luxuriate on the serpentine. The serpentine lies to the west, reared up in the magnificent cliffs of Mullion and Kynance coves, but the main body of the upheaved plateau consists of another volcanic rock called gabbro. The serpentine is so called because it has something of the glaze and greenness of a snake's skin. The Lizard rocks have long been an object of interest and dispute among geologists. For a study of them I must refer to the papers of Mr. T. Clark in the _Transactions of the Polytechnic Institution of Cornwall_. The most casual visitor must be struck, if in Meneage at the season of flowering, with the abundance of the beautiful Cornish heath (_Erica vagans_), which in growth and general appearance cannot for a moment be mistaken for the common heath. The Rev. C. A. Johns says of it in his _Week at the Lizard_:-- "The stems are much branched, and in the upper parts very leafy, from two to four feet high. The flowers are light purple, rose-coloured, or pure white. In the purple variety the anthers are dark purple; in the white, bright red; and in all cases they form a ring outside the corolla until they have shed their pollen, when they droop to the sides. On the Goonhilley Downs in Cornwall these varieties of heath grow together in the greatest profusion, covering many hundreds of acres, and almost excluding the two species so common elsewhere." It flowers from July to September. Another heath found there and near Truro is the _Erica ciliaris_, with bright purple flowers of oblong form; it is by far the most beautiful of our English heaths. The flowers are half an inch in length, growing down the upper part of the stem, and the leaves are delicately fringed with hairs. It has a somewhat glutinous feel. It is rare except in Cornwall. A rare plant, and pretty withal, is the strapwort (_Corrigiola littoralis_), trailing among the shingle on the bar of Loe Pool. It has minute white flowers and glaucous leaves. The plant has a curious habit of shifting its quarters almost every year from one part of the shore to another.