Page:A Voyage of Discovery and Research in the Southern and Antarctic Regions Vol 2.djvu/444

400 the appearance of so many imbedded cannon, pointing down on the road at a considerable angle. Along many of the cliffs on the banks of the Derwent, I observed dark shades and lines of dust, indicating traces of coal. West of the town of New Norfolk is a limestone quarry.

In my excursion to Tasman's Peninsula, this singular fossiliferous formation, so called by the colonists, particularly attracted my attention. It is a kind of argillaceous deposit, situated a little to the northward of the neck, or low sandy isthmus, connecting Forrester's with Tasman's Peninsula; having an inlet of Norfolk Bay on the west, and Pirate's Bay on the east. The latter is bounded by argillaceous cliffs, somewhat steep, and of moderate height; at the base of which the wash of the sea has formed a sort of platform, on which it breaks at high water. The siliceous clay forming this platform is very remarkably divided by the most symmetrical partings into slabs, varying in length and breadth, having their margins frequently bordered in strong relief. The dimensions of those I measured were from three to nine feet long, and from four or eight inches, to six feet broad, and others were eighteen inches square. These divisional planes had a general bearing of E. by N. with a perfectly geometrical parallelism in relation to each other.

The curious structure displayed here may, probably, be due to some re-arrangement of the particles coming under the influence of electro-magnetic forces whilst passing into a solid state, giving a definite direction to the ordinary partings which argillaceous depositions frequently present when contracting under sudden changes of temperature during the process of consolidation.

Spirifera vespertilio and Spirifera avicula are profusely imbedded in this deposit.

The argillaceous cliffs at Point Puer, Port Arthur, contain the same species of shells, with Pachydomus globosus.