[Footnote 226: For recent contributions to the Geology of the Faroe Islands, see Prof. James Geikie, _Trans. Roy. Soc. Edin._ vol. xxx. (1880), p. 217, where the banding of the basalts is noticed; Prof. A. Helland, _Dansk. Geografisk. Tidskr._ (1881); R. Bréon, _Notes pour servir à l'étude de la Géologie de l'Islande et des Isles Faeroe_ (1884); Mr. J. Lomas, _Proc. Geol. Soc. Liverpool_, vol. vii. (1895), p. 292. Various writers have treated of the petrography of Faroe, particularly A. Osann, _Neues Jahrb._ (1884), vol. i. p. 45, and M. Bréon in the volume here cited.] 5th. Ordinary flow-structure, save in these banded lavas, is rather rare among the plateaux. It may, however, be occasionally observed, where there is no distinct banding. On a weathered surface it appears in fine, widely parallel streaks, which are sometimes wavy, puckered and broken up, as in rhyolites and felsites, while the porphyritic felspars are arranged with their long axes in the direction of flow. A good example of these characters may be seen on the summit of the Dùn Can--the remarkable truncated cone which forms the highest point on the Island of Raasay. The rock is a black olivine-basalt, partly amygdaloidal, with zeolites filling up the cavities, and its flow-lines are prominent on the weathered faces where they lie parallel to the general bedding of the lavas. Another illustration may be observed in the basalt already cited from Loch-na-Mna, in the island of Eigg, where the rock presents in places a remarkable streaky structure which, though hardly visible on a fresh fracture, reveals itself on a weathered face in thin nearly parallel ribs coincident in direction with the upper and under surfaces of the mass.