154 



THE AMEEICAIS MONTHLY 



[August, 



in the Middle Ages as a bviilding 

 stone, the palace and Abbey of West- 

 minstei" having been mainly con- 

 structed of it from the quarries of 

 Merstham, though passing under the 

 general term of ' Ryegate Stone.' It 

 \vas also used for effigies, and for in- 

 door purposes ; kept free from damp, 

 it was durable, and presei'ved a sharp 

 edge in its working. Dissolving the 

 lime from it, the deposit shows us 

 nearly half to be finely comminuted 

 quartz, some few particles of flint 

 equally fine, and a large quantity of 

 silicified casts of many species of for- 

 aminifera, and particularly of one 

 very minute in size, -which I assume 

 to belong to the Globiogerinas. Other 

 forms I am not acquainted with, look 

 like portions of very minute encri- 

 nites, but I must profess my igno- 

 rance ; and as the subject has been 

 worked out by Ehrenberg, I suppose 

 it is well understood. I may remark, 

 however, that these silicifications have 

 in composition a remarkable resem- 

 blance to that of chalk flint, which 

 would rather support the view of Mr. 

 Ha-wkins Johnson, that the latter was 

 of organic origin. As a factor of the 

 sand of our coasts, this deposit could 

 play but a small part, and may there- 

 fore be dismissed for the consideration 

 of the lower bed. 



This bed is known as the ' Shank- 

 lin ' Sand, from its being so well rep- 

 resented in that locality, and has at 

 its base a well-known building stone 

 called ' Kentish Rag.' Taking some 

 seams of sand found with it for ex- 

 amination, I find one-half to be com- 

 posed of quartz, the other of dark 

 opaque grains, which I cannot iden- 

 tify. I have examined also other 

 specimens from different beds, but 

 the result is the same. 



I will now, in conclusion, take a 

 retrospective glance at the facts pre- 

 sented before you. The one great 

 fact is the predominance of quartz. 

 It is only in the two lower beds, ' the 

 Green Sand,' that this material is not 

 in excess of every other, and even in 

 them it constitutes one-half, and in 



neither case does the chalk flint ap- 

 pear but in very small quantities. 

 That it should be almost absent in 

 the gravel composed of flint shingle, 

 and from sand veins found in the very 

 midst of its rolled pebbles, is very 

 surprising. The quartz sand, of the 

 gravel, has larger grains by three or 

 four diameters than in any other lo- 

 cality named, and has many points of 

 interest to study. It is well rounded 

 by attrition, which is not the charac- 

 ter seen in many other examples. It 

 seems to be often in a state of appa- 

 rent decomposition, and is covered 

 by an oxide of iron, which requires, 

 to be removed by acid for its more 

 complete examination. In the Bag- 

 shot Sands we should scarcely have 

 expected to find chalk flint grains, 

 but they appear in the proportion of 

 4 to 7 per cent., and in this deposit 

 the quartz has some rounding of the 

 edges, bvit not giving a character to 

 the whole. Nevertheless, it more re- 

 sembles that of the superficial gravel. 

 I alluded, at the commencement of 

 my paper, to the sand found at Brid- 

 lington, and particularly that at Low- 

 estoft, on account of the comparison 

 instituted between it and that of Ab- 

 erdovey. But it would be a very im- 

 perfect argument, after so many speci- 

 mens from ancient deposits, not to 

 notice some of those now forming. 

 By the kindness of Mr. Priest, I have 

 been enabled to examine examples of 

 the sands of Cromer and those of 

 Ramsgate. They are composed of 

 fine examples of rounded quartz par- 

 ticles, with chalcedony and a few 

 other substances, some of calcareous 

 origin. That at Cromer is resplend- 

 ent in its quartz, when beneath the 

 niicroscope, and is, perhaps, the finest 

 of all my examples, extremely beau- 

 tiful as an object by polarized light, 

 and, I think, instructive in its illus- 

 tration, could one pursue the ques- 

 tion further than at present I propose 

 to do. From Hythe, in Kent, I had 

 some sent up to me from high-water 

 mark, thinking it might there be more 

 free from the engrossing quartz. But 



