366 Proceedings of Societies. 



Coniston Lake, in "Westmoreland. From a hasty examination of these, 

 Mr Greg was led to suppose that he had found a new substance, and the 

 analytical result proved that he was right. I found the mineral to be an 

 oxalate of lime, differing from Whewellite in having six additional atoms 

 of water of crystallization. Associated with these white crystals was a 

 purplish red substance, which, appearing to me to be new, I submitted 

 also to analysis, when it proved to be an oxalate of potash, with ten atoms 

 of water of crystallization. The colour was due to some oxalate of co- 

 balt. It is always desirable that a mineralogist should be able to account 

 for the occurrence of every substance which comes under his notice. This 

 is more especially the case when the substance is of an organic nature, and 

 in general we have little difficulty in satisfactorily explaining even such 

 occurrences. The mineral Humboldtine, for instance, being found either 

 embedded in lignite, or associated with decomposing succulent plants, leaves 

 no room for doubting that, as it is organic in its matrix, so also it is or- 

 ganic in its origin. I am afraid, however, that our ingenuity will be taxed 

 rather severely to account for the three other oxalates which we are now 

 acquainted with, two of these having been found deep in the womb of 

 earth, associated with a metallic lode. I think there can be little question 

 that they are of secondary formation, having resulted in some way or other 

 from the operations connected with the working of the mine ; but I pro- 

 fess to be perfectly unable to offer any explanation which appears even 

 to myself to be satisfactory. One theory has been brought forward, — 

 a theory which I cannot but dissent from ; it is, that the minerals were 

 originally bi-carbonates, — that metallic potassium having been brought 

 into contact with them, an atom of oxygen was abstracted, the result 

 being necessarily oxalates. This does not appear satisfactory : neither 

 bi-carbonate of lime or of potash have yet been found in nature ; and I 

 cannot place myself among those who, whenever they wish to account for 

 volcanic action, or to get out of any difficulty, call in the aid of metallic 

 potassium. I am very far from thinking that no satisfactory theory can 

 be brought forward, but I am content for the present to look upon the oc- 

 currence of these oxalates as one of many proofs that as yet we know 

 but too little of the operations carried on in nature's laboratory. The 

 first of these minerals has been named by Mr Greg Conistonite, from 

 the locality ; and the second Heddlite, after the analyst. 



2. On a Raised Sea Bottom, near Filliside Bank, between Leith and 

 Portobello. By Hugh Miller, Esq. 



3. Exhibition of a Collection of Liasic Fossils from Pabba and Shje. 

 By Archibald Geikie, Esq. 



Mr Geikie laid on the table the fossils he had collected, which he illus- 

 trated with the following remarks : — The Isle of Skye is an object of 

 special interest to the geologist, from its containing in tolerable abun- 

 dance the remains of the Liasic formation, — one which occurs in but 

 unfrequent patches throughout the whole extent of Scotland. The 

 Lias, as developed in that island, stretches from shore to shore in a band 

 about seven or eight miles in length, by from two to five in breadth. 

 Over the greater part of this extent a dark peaty soil covers the strata, 

 so that they are seldom discernible, save where channelled by some moun- 

 tain torrent. The best exposures are therefore to be found at the extre- 

 mities of the belt. Broarlford Bay, on the east, affords a general section 

 of the formation. The beds are there free from the dislocating effects of 

 trap dykes, and dip gently under the waters of the bay at an angle of 5°. 

 The lowest members of the series are found at the village of Lussay, rest- 

 ing uncomfortably upon the red sandstone of Sleat. They consist of con- 



