386 PHILOSOPHICAL TRANSACTIONS. ^ [anNO idSJ. 



or lead 3 inches thick, as soon as it is put in the focus, melts away in drops, 

 and held there a little time is in a perfect fluor, so as in 2 or 3 minutes to be 

 quite pierced through. 4. A plate of iron or steel, placed in the focus, is im- 

 mediately seen to be red hot; and soon after a hole is burnt through. 5. Copper, 

 silver, and the like, applied to the focus, melt, in 5 or 6 minutes. 6. Things 

 not apt to melt, as stones, brick, and the like, soon become red hot like iron. 

 7. Slate at first is red hot, but in a few minutes turns into a fine sort of black 

 glass, of which if any part be taken in the tongs, and drawn out, it runs into 

 glass threads. 8. Tiles which had suffered the most intense heat of fire, in a 

 little time melt down into a yellow glass, as do, Q. Pot-shreads, not only well 

 burnt at first, but much used in the fire, into a blackish-yellow glass. 

 10. Pumice-stone, said to be that of burning mountains, in this solar fire, 

 melts into a white transparent glass. 1 1. A piece of a very strong crucible put 

 in the focus, in 8 minutes was melted into a glass. 12. Bones turned into a 

 kind of opake glass, and a clod of earth into a yellow or greenish glass. 



It was tried what effect the beams of the full moon, concentred with this 

 speculum, would have, at the time when she was at her greatest altitude ; but 

 there was not found any degree of heat, though the light was not a little 

 increased. 



Mr. Hook was of opinion, that if such a speculum were made of many feet 

 diameter, its effects must needs be prodigious ; and might be of great use in 

 perfecting the art of pastes or factitious jewels, which require the most intense 

 degree of heat, to bring them to an exact mixture. He conceives such a one 

 might be made very large for a small price, being hammered out of a copper 

 plate, and tinned over with a mixture of tin, lead, and tin-glass, jvhich is found 

 to bear a very good polish. 



jiccount of some Saxon Coins found in Suffolk, Communicated by Sir P. S, 



R. S. Soc. N° J 89, p. 356. 



In May l687, at Honedon, near Clare in Suffolk, as the sexton was digging 

 a grave in the church-yard, he met with a skull ; and near it his spade broke 

 a yellow earthen pot, wherein were many silver pieces of Saxon money, the 

 inscriptions on which are so various, that there are scarcely any two alike, 

 though they are generally of the same size, viz. that of a silver groat, and 

 about the same weight. I guess this variety of inscriptions arises from the 

 many masters of the mint who were appointed to coin money in several places, 

 and who might each of them have a different stamp : and I find this conjecture 

 countenanced by a passage in king ^thelstan's laws, printed by Lambard. 



