Part of Two Letters from Dr James Brewer to Dr Sloane, concerning Beds of Oyster-Shells Found Near Reading in Barkshire

I. Part of two Letters from Dr James Brewer to Dr Sloane, concerning Beds of Oyster-shells found near Reading in Berkshire. Jan. 13. 1699. I Ask your pardon that I am so late in performing my promise in sending you the Oyster-shells. As to the original of them, 'tis a province too nice and difficult for me to solve. You see they have the entire figure, form, and matter of Oyster-shells, and, no doubt, they are such. But how they should come to the place where I dug for them, and where for so many succeeding Generations they have been found, I leave you and other Philosophers to determine: They do encompass nigh 6 Acres of ground: Just above the Layre of these Oysters there is a greenish Earth, or rather Sand, and under them there is Chalk. Sir, I have often seen in several Chalk-pits a few scatter'd Oyster-shells. But in this place they are as it were one continu'd Body, and in an even line. Through the whole circumference between 5 and 6 Acres of ground. I wish at your leisure hours, that you would be so kind to afford me a line or two of your thoughts as to these Shells, and of the use you likewise promised to acquaint me, that they might be in practice more than common Alkali's. You know we have no Sea near us, and therefore it seems the more strange, how these Shells should be placed in such a compass of Ground. SIR Sir, In Answer to your last, be pleased to take the following account, the observations which I personally made, were with all the exactness as the subject and place would admit. The circumference then, where these Oyster-shells have been digg'd up, and found, contains (as I before hinted to you) as is judg'd, between 5 and 6 Acres of Land. The foundation of these Shells is a hard Rocky Chalk, and above this Chalk the Oyster-shells lye in a bed of green Sand, upon a level, through the whole circumference, as nigh as can possibly be judged; this Stratum of green Sand and Oyster-shells is (as I measured) nigh 2 foot deep. Now immediately above this Layre, or Stratum of green Sand and Shells, is a bed of a bluish sort of Clay, very hard, brittle, and rugged, they call it a pinny Clay, and is of no use. This Bed, or Layre of Clay, I found to be nigh a yard deep; and immediately above it, is a Stratum of Fullers-earth, which is nigh two foot and a half deep; this Earth is often made use of by our Cloathiers: and above this Earth is a Bed, or Layre, of a clear fine white Sand, without the least mixture of any Earth, Clay, &c. which is nigh seven foot deep: then immediately above this is a stiff red Clay, (which is the uppermost Stratum) of which we make our Tiles. The depth of this can't be conveniently taken, it being so high a Hill, on the top of which hath been, and is dug, a little common Earth about two foot deep, and immediately under appears this red Clay that they make Tiles with- al; as the Gentleman that lives on the spot tells me: I should also have acquainted you that this very day with a Mattock I dug out several whole Oysters with both their Valves, or Shells lying together, as Oysters before opened, in their Cavity there is got in some of the prementioned green Sand. These Shells are so very brittle, that in digging for them, one of the Valves will frequently drop from its fellow, but 'tis plainly to be seen that they were united together, by placing the Shell that drops off to its fellow Valve, which exactly corresponds; but I dug out several that were entire; nay, some double Oysters with all their Valves united. Sir, thus I have endeavoured to answer your Queries, and I hope you'll excuse all defects and errors. But if in this information there may be any thing of use, or satisfaction to you, &c. I have my desired end: The Account that I have here given you of these Shells, and Strata's of Sand, Clay, &c. is what I yesterday and this day observed, and try'd on the spot, therefore you may depend on the faithfulness of it. II.