''igS PHILOSOPHICAL TRANSACTIONS. [aNNO IOQJ . 



often an attendant on thunder and lightning. It is well known, in our artificial 

 congelations, that a mixture of snow and nitre, or even common salt, will 

 cause a present and very sudden congelation of water. And the same in clouds 

 may cause that of hail-stones. And the rather, because not only in those 

 prodigiously great, but in common hail-stones, there seems something like 

 snow, rather than ice, in the middle of them. And, as to those in particular 

 so very large as to weigh half a pound, or three quarters of a pound, supposing 

 them to fall from a great height; it is very possible, that though their first con- 

 cretion, upon their sudden congelation, might be but moderately great, as in 

 other hail ; yet in their long descent, if the medium through which they fall 

 were alike inclined to congelation, they might receive a great accession to their 

 bulk, and divers of them incorporate into one, like as in those icicles before 

 mentioned. 



Effects of a violent Storm on the Rivers of JSorth America. By Mr. Scarburgh, 



ofAcomach. N° 23 1 , p. 659. 



Oct. 19, 1693, in the North-American provinces, there happened a most 

 violent storm, which stopped the course of ancient channels, and made other 

 new ones; so that between the bounds of Virginia and Newcastle, in Pennsyl- 

 vania, are made many new navigable rivers for sloops and small vessels. 



On the Damage that happened in the Isle of Portland, Feb. 3, 1695-6. Com- 

 municated by the Hon. Sir Robert Southwell, F.R.S. N° 231, p. 659. 



The great pier is quite demolished, and filled up with rubbish ; and the rocks 

 that lay about 40 yards off in the sea, at the pier head, are raised above water, 

 so that there are no hopes of making good that pier again. And the roads lead- 

 ing to that pier from the quarry, are turned upside down, and sunk at several 

 places about 30 feet. Also the way leading to the north or little pier, is under 

 the same circumstances, and the pier cracked in several places. The earth is 

 slid into the sea between the two piers, near 100 yards, and is still working off 

 into the sea. It is conjectured that this proceeded from a great quantity of 

 rubbish thrown over the cliff, upon a clayey foundation, which the violence of 

 rain softened, and made it give way ; and not by earthquake, as some report. 



Part of a Letter from Mr. Thoresby, (Leeds, July 10, 1697,; to Dr. Martin 

 Lister, F.R.S. concerning T\vo Roman Altars lately found in the North of 

 England : xvilh Notes on the same, bif Tho. Gale, D. D. and F. R. S. 

 N°231, p. 663. 



One of these altars was taken out of the Roman-wall, not far from Chollar- 



