Part of a Letter from the Right Honble Robert James Lord Petre, F. R. S. to Martin Folkes, Esq; P. R. S. concerning Some Extraordinary Effects of Lightning

but being disappointed, they soon spread a Report over the Country, that by a Discovery made by some antient Writings, we dug there for Treasure, by which we were greatly enriched: To prevent the further Concourse of the People, &c. we were glad to fill up the Trenches, and leave the other Tumuli unexamined. N. B. The Middle Tumulus is about Nine Yards in Diameter, and the lesser about Eight Yards each at the Plain. VIII. Part of a Letter from the Right Hon'ble Robert James Lord Petre, F. R. S. to Martin Folkes, Esq; P. R. S. concerning some extraordinary Effects of Lightning. SIR, Brook-street, June 24. 1742. Read June 24. 1742. ON Tuesday Morning, between Three and Four o’Clock, we had at Thorndon some of the most terrible Thunder I ever heard; and, indeed, by the Effects of it, I have Reason to conclude, that it was very near us, as well as by the Noise, to which I really think no other Thunder I ever yet had any Notion of, could be compared. It has beat down a Chimney at a Farm-house just by, and the Lightning has also struck Two large Oaks in my Park, which stand about Forty or Fifty Feet apart. In one of them I do not observe any thing much different from other Trees which I have before seen struck with Lightning; the only thing that seems remarkable, is, that the greatest Damage ap- pears to be done to the East Side of the Tree, although it is certain, that the Storm all came from the South-West. This Tree is extremely shattered, and split from the Top to the Bottom; and on the South-West Side, just by the Root, there is a large Hole made in the Ground, about Six or Seven Inches Diameter, and about a Foot or Fifteen Inches deep. But in the other Tree, I think, there is something more particular; for there, without shattering or splitting the Tree in the least, or so much as disturbing a single Branch, although there are a great many upon it, the Lightning has taken off the Bark about Five Inches wide, in a complete spiral Line, from about Forty Feet high, down to within about a Foot of the Ground, where the Width diminishes to about Two Inches, and so goes quite off: In the Centre of these Five Inches, it has entered the Wood about Three-fourths of an Inch deep, and about an Inch and half wide: This Hollow it has in great part cleared out entirely, and the rest is left hanging like Pieces of broken or untwisted Ropes; this Hollow also diminishes near the Ground, and dies quite out exactly at the Ground: The spiral Line is exactly regular, and goes just once round the Tree, or but very little more, and, as near as I can observe, is exactly of an equal Width all the Way. The Surface of the Bark of both the Trees is remarkably touched for about Ten Feet from the Ground, as if it were shot all over with Small-shot, each of which seems to have taken off little Scales or outside Pieces of the Bark, from an Inch and half or Two Inches broad and long, to a quarter of an Inch. I will add no more, than only to wish, that this Account may prove any any thing new or agreeable to you, to desire you to excuse the great Hurry in which it is wrote, and to assure you, that I am very sincerely, SIR, Your faithful Humble Servant, Petre. N. B. Effects of Lightning, like this, were observed by Sir John Clark. See Philosophical Transactions, No 454. p. 235. IX. An Account of a Meteor seen at Peckham, Dec. 11. 1741. by Tho. Milner, M.D. Read June 24. December 11. 1741. at Seven Minutes past One in the Afternoon by the common Clocks, a Globe of Light, somewhat larger than the horizontal Full Moon, and as bright as the Moon appears at any time while the Sun is above the Horizon, instantaneously appeared, in a blue clear Sky, about the S. S. E. moving towards the East with a continual equable Motion, and leaving behind it a narrow Streak of Light, whiter than the Globe itself, throughout its whole Course. Towards the End it appeared less than at the Beginning of its Motion; and within Three, or at most Four Seconds, it suddenly vanished. Its apparent Velocity was nearly equal to half the Velocity of those usual Meteors commonly called falling or shooting Stars: This may be thought an indeterminate way of expressing its Velocity, as those falling Stars vary in the Swiftness of their Motions; but if such be understood as have