520 . PHILOSOPHICAL TRANSACTIONS. [aNN0 1681-2. 



and bole are no where that I know of to be found with us in England but in 

 that tract; being fossils peculiar to those mountains. Of these jet rings some 

 are plain, and others wrought, but all of them of an extraordinary size, being 

 at least 3 inches diameter, and yet the inward bore is not above an inch and a 

 half, which makes them too little for the wrists of any man, as they are much 

 too large for the fingers ; so that probably they were never worn as armilla or 

 annuli, bracelets or rings. And since we are upon the subject of plastics, or 

 the Roman clay-work, we cannot but take notice of the opinion of Cambden ; 

 who will have the obelisks at Burrow-Brigs in this county, to be artificial, 

 when in truth they are nothing less, being made of one of the most common 

 sort of stone, viz. of a coarse rag or milstone-grit; but doubtless the size of the 

 stone surprized him, either not thinking them portable, or perhaps not any 

 English rock fit to yield natural stones of that magnitude ; but that they are 

 Roman monuments I suppose none doubts, because pitched here by a very re- 

 markable and known Roman station, Isurium. 



And then consider what trifles these are, compared with the least obelisks 

 at Rome. And as to the rocks whence they might be hewn, there are many of 

 that stone near the. river Nid, and on the forest of Scarsbourg ; and a little 

 above Ickley, another Roman station, within 1 6 miles of Burrow-Bridge; there is 

 one solid bed of this very stone, the perpendicular depth of which only will 

 yield obelisks, at least 30 feet long. And yet at Rudstone, near Burlington in 

 the Yorkshire woulds, full 40 miles wide of these quarries, is an obelisk of the 

 very same stone, shape, and magnitude, of these before-mentioned. And it 

 must be observed that almost all the monuments of the Romans with us were of 

 this sort of stone. 



A Letter of Mr. Anthony Leuwenhoech, dated from Delft, Nov. 4, l68l ; 

 containing an Account of several new Discoveries made by him this last Summer. 

 Philos. Collect. N°4, p. 93. 



I have formerly written that the skin of the hair of an elk, hart, &c. was 

 made up of globules, and that I had also examined our own hair, which I then 

 judged to be composed of globules. I. have, since written that our hair has a 

 bark like trees, composed of globules, whose irregularity is caused by being 

 whilst soft squeezed out through the skin. The innermost parts of the hair are 

 made up of threads. But many supposing hair to be hollow, others to have 

 marrow like a bone ; made me draw the figure of a hog's bristle, to show that 

 what hoUowness does sometimes appear in the hair, which some fancy to be 

 marrow, is nothing but the inward clefts of the hair. For the hair grows not 



