Fisher — Notes on Clacton, 213 



purpose of this Magazine ; for all inquiries respecting metamorphic 

 rocks must rest on such chemical data primarily) ; and, also, I 

 should be grateful to any mineralogist who would give me some 

 tenable clue, or beginning of clue, to the laws which affect the 

 modes of crystalline increase ; that is to say, which determine 

 whether a prism of quartz or calcito shall increase at the extremities 

 or at the flanks, or consistently on both, or inconsistently at 

 different parts of the prism ; and, especially, by what law stellar or 

 or roseate aggregations take place, instead of confused ones, in 

 groups of crystals ; and by what tendencies some minerals, fluor for 

 instance, are limited in their expansions of the cubic or other com- 

 mon form, while others, such as salt and the oxide of copper, are 

 enabled to shoot unlimitedly into prismatic needles ; and others, like 

 sulphide of iron, will form in solid crystals on the outside of calcite 

 and in stellar acicular groups within it. If I can get some help in 

 this chemical and microscopic part of the work, which I cannot do 

 myself, I have hope of being able to give something like a service- 

 able basis for future description of the two great groups of calcite 

 and silica, and the modifications of iron which colour the con- 

 cretions of marble in the one case, and of agate in the other ; and I 

 should do this piece of work with, perhaps, more zeal and care than 

 another person, owing to its connection with my own speciality of 

 subject, by the use of these two earth-products in the arts, and the 

 foundation of much of what is most beautiful in architecture, and 

 perfect in gem-engraving, on the accidents of congelation which 

 have veined the marble and the onyx. J. Ruskin. 



Denmark Hill, 22nd April, 1868. 



IV. — A Few Notes on Clagton, Essex. 

 By the Rev. 0. Fisher, MA., F.G.S. 



THE following is taken from a MS. by the late Mr. John Brown, 

 E.Gr.S., of Stan way, Essex, and given by him to Professor 

 Henslow, who gave it to me. The actual measurements are not 

 mentioned, but I believe the scale to be about an eighth of an inch 

 to a foot. It is valuable as having evidently been made when the 

 beds were better seen than usual. Moreover, the constant waste of 

 the cliff alters the section continually. 



"1. Vegetable Soil 



2. Loam with interspersed flints, both rounded and angular, white 

 quartz pebbles, and Quartz Sandstone in boulders 



3. Freshwater shells in red sand 



4. Peat, 



5. Marine and freshwater shells , 



6. Peat, with subordinate and interrupted beds of marine and fresh- 

 water shells (tooth of water rat) 



Marine and freshwater shells 



Bones of the larger mammalia, generally found between the cliif 

 and low-water-mark, freshwater shells, trunks of trees, nuts, and 



seeds, as we find in tbe upper beds : no marine fossil shells 



London clay at the j unction of low- water-mark " 



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