81 
of Edinburgh^ Session 1862 - 63 . 
bulk more than one-fourth greater than before, an increase nearly 
four times as great as that of water in freezing. This expansion, 
prevented from developing itself freely, has accumulated at the 
point of least resistance, and forced up the Kalkberg just like the 
plug of ice which rises through the fuse-hole of a mortar-shell when 
filled with water and frozen. 
The origin of the sulphuric acid cannot be traced. Heat, pres- 
sure, and strong brine have all been proved sufficient to effect the 
deposition of the sulphate of lime in an anhydrous state. 
The expansion through metamorphism must have occurred after 
the deposition of the chalk, and before that of the miocene clay, the 
chalk having been disturbed, and the clay thrown down on it after 
its disturbance. 
III. That the age of these gypseous and saline deposits, though 
a difficult question, can be determined. 
No borings have been carried through the anhydrite to show on 
what it rests. Evidence of age therefore lies in the fossils of the 
overlying strata, which, resting on the gypsum, have been brought 
up along with it. These strata are minute in extent, but abound 
in fossils — chiefly casts. They indicate the Upper Trias, but the 
particular member of it to which the beds are to be assigned has 
been keenly debated. Very recently, however, the discovery of five 
specimens of Geratites nodosus have, in connection with the rest of 
the evidence, and especially as associated with Myophoria pes anseris^ 
given the preponderance in favour of the Lettenkohl. This is a 
subordinate formation now admitted to exist ; but whether to be 
ranked as the highest of the Muschelkalk or the lowest of the 
Keuper, or a transition link between the two, is doubtful. Its flora 
connects it with the Keuper, its fauna with the Muschelkalk. In 
the Liineburg beds no vegetable remains have been found, and the 
want of these renders the relation of these beds to the Keuper more 
obscure. The absence of such vegetable remains is indeed a char- 
acteristic of the Muschelkalk ; but this is but a negative resem- 
blance, 'and its force is counteracted by the absence in the Liineburg 
beds of such distinctive fossils of the Muschelkalk as the Encrinites 
liliiformis^ Nautilus hidorsatus, Terebratida vulgaris^ &c. 
The question then must be determined by the Myophoria pes 
anseris and the Geratites, both of them interesting in themselves 
