Part of a Letter from Mr Ralph Thoresby, F. R. S. to the Publisher, concerning Severol Observables in His Musaeum, Near Leeds in Yorkshire

maining in the Cranium but a small quantity of black putrid Matter. This to the best of my remembrance is the summ of all. He had neither Spasmus nor Convulsions of any part all the time of his illness. IV. Part of a Letter from Mr Ralph Thoresby, F. R. S. to the publisher, concerning several observables in his Musæum, near Leeds in Yorkshire. SIR, Remember that upon perusal of the Catalogue of the Natural Curiosities in my poor Musæum, you desired a more particular Account of the Skin of the Fishes Stomach from the Indies; of the Crystal, and the ways of its Concretion; of the Iron turned into Ore; and of the Otoedra from the Copper Mines in Sweden. The first was given me by Mr Robert Midgley of this Town, an ingenious Apothecary, who made 5 Voyages as Surgeon into the East Indies. It is the outward Skin of the Maw of a Fish that was taken at Macassar, Febr. 1681, and was given him at Batavia by a Dutch-man, who took it out of the Fish. That the Fibres or Vessels do curiously and naturally resemble a Tree, with its Stem, Branches, Leaves, &c. will appear by the enclosed figure of it, which, tho but slenderly performed, is the best I have time to do now, and is so like the Original that it will save the labour of any further description, (for 'tis exactly the bigness and shape of this Draught,) save that the Skin is very thin, whitish, and transparent, and the Veins that compose the Stem and greater Branches, are now rather Black than dark Red, as I presume they were at first, the Leaves a sort of dark and faded Green variegated. See Tab. 7. fig. 1. The Crystal with other Natural Curiosities, was given me by the Learned and Ingenious Dr. Jabez Cay of Newcastle, who brought it from Milan: And because his description will be much more accurate than I can pretend to, I will make bold therewith, only promising his arguments upon a sort of Spar within a Flint, sent me at the same time. That within the Flint (says he) seems to differ from the rest of its substance, and somewhat to resemble Spar: Tho after all, Spar being nothing else but a Cristalline sort of Lime-stone, it differs not from Flint in reality, but only in appearance, i.e. in the manner of Concretion, tho if the inclosed Matter had in its nature differ'd from the rest of the Stone, the thing had not been very uncommon, it being usual enough for Stones (especially those of a globular or oval form) to have Coat upon Coat, and those Coats sometimes very different one from another, some of them soft, some hard, nay, sometimes after a long space of time, one of these Coats will shrink from another, after the manner of a Kernel when the Shell grows dry; And then if the enclosed substance continue soft and marly, they call that Stone Geodes; but if stony, it makes one of those Rattling Stones that are known by the name of the Ætites, or Eagle Stone. To confirm what I have here advanc'd, it were easie to prove by many instances that it is no unusual thing for Stones to inclose Substances of a very differing nature from themselves; the Shells in the Suffex Marble herewith sent you is one proof of this matter, and the Stones found in our Coal-pits, and known amongst the Workmen by the name of Cat-heads, may serve for another; they are found in a particular Stratum near the Coal, and enclose a Fern, or sometimes Polypody Leaf in the middle of them; and for that reason being struck with a Hammer very readily break there: I think they are a sort of Iron Stone, akin to that which they call in Staffordshire Ballmine, and Dr. Lister, Minera ferri pilæformis; they have it upon the Western Coasts near Whitehaven, and call it there by the name of Cat-scamps. I have seen of it too upon the Yorkshire Coasts in Robin Hood's Bay: You may if you please, till I find a better name, call it Lapis minerae ferri, Pilæformi similis, in cujus Meditulio, unum vel plura filicis folia representantur. (I have since from my said worthy Friend receiv'd Specimens of both sorts.) And to give you an instance that one and the same piece of Rock does not always shoot into Stone at one and the same time, but first one part of it and then another, and they too not after the same regular manner, but irregularly enough, I have sent you a piece of Rock Crystal, where you may easily observe the modus concrecendi in the middle to have differed from that of the outside, nay sometimes I have seen in the middle of some transparent Stones a small drop that never would take the solid form of the rest of the Stone at all. The 3d. Curiosity was also sent me from the same very kind Friend Dr. Gay; 'tis a piece of an Iron-bolt (2 inches long) found in a Stone Quarry, now return'd into Iron Ore again; this being a Property that Iron has, and no other Metal, as Dr. Lister observes in his journey to Paris. 4thly, The Copper Ore so regularly shot into an Octaedrous form, was sent me from Sweden by Mr. William Sykes of Stockholm Merchant, it has 8 solid Triangles, and consequently 6 angular points, and is as well of the bigness as figure of the inclosed draught of it; my said Cousin receiv'd it from the Copper Groves at Fallum, where very many of the same form were then found, tho he cannot now get another of them, See Tab. 7. Fig. 2.