Inverted Carbonate of Lime

Where there is much Carbonate of Lime, as at Portland Island, there may be expected much variety. Thus there are some varieties of that sort used for building, see tab. 8; and also some of the crystallized, see tab. 143, 144. As well as tab. 174, the present specimen is rather a whimsical one, showing how nature sports, yet conformable to a certain regularity.

The last aggregation of molecules had apparently formed nuclei of inverted rhombs, arranging themselves something like an inverted pyramid—see left hand figure, tab. 174. The present specimen has a great variety of three-sided pyramids, nearly regular, or with prominent sides, (see the left hand tower figure,) and consequently concave faces, (see the right hand figure,) and with various kinds of bases, as in the other separate figures.