VOL. XXXIII.] PHILOSOPHICAL TRANSACTIONS. 105 



and after that grew narrower; in both of them, the matter divided into two 

 parts, and formed horizontal cavities about 3 inches diameter. In one was 

 found a very hard glazed stone, of about 10 inches long, 6 wide, and 4 in 

 thickness, cracked in two; others it could not pierce, but was turned here and 

 there out of its course, but left not the least blackness, or other discolouring 

 any where. As to the knife, it was not the blade but the handle and the hinge 

 which were shivered in pieces. Near the wounded sheep, the ground was torn 

 up near 1 yards round. 



One James Marshal of the same town said, that in the middle of the same 

 storm he received a blow on his hat, which rattled like shot through the 

 branches of a tree; it beat in the crown a little, without penetrating it: he 

 staggered, and was giddy for two days afterwards. Two of his sons were at the 

 same instant both struck down to the ground, and stunned a little, but presently 

 came to themselves, and had no wound. Query, whether this may not be ac- 

 counted for, by supposing the flame to rarefy the air, and make a sort of 

 vacuum about one, into which when it returns again, it gives the likeness of a 

 stroke with a beetle, as he expressed it. Perhaps a wind-gun, with compressed 

 air, would have the same efi^ect, and might easily be tried on a dog, or such 

 like animal. 



Of Magnetkal Pmvers. By M. Muschenhroek* N^SQO, p. 370. From the Latin. 



M. Muschenhroek wished to try, whether loadstones operate on each other 

 at different distances, according to a certain proportion; and he saw in the Phil. 

 Trans, N° 335, that Mr. Hauksbee had thought of the same thing; but that 

 he had made the experiments with a loadstone and needle, that could not satisfy 

 accurate inquirers; whence, though he concludes in these words: ' I see no 

 reason to doubt, but the proportions of this power will be regular, and corre- 

 spond to the different distances;' yet Dr. Taylor, Phil. Trans. N° 334, 

 repeated the sam.e experiments, and made observations differing from those. 



M. Muschenhroek attempted the same thing in a quite difterent manner; he 

 thought, that if he took two magnets, and hung one of them by a thread, at 

 different distances above the other, and if he tied the end of the thread to a 

 balance, he might weigh the quantity of the force with which the magnets 

 would act on each other; which succeeded accordingly. He took a very nice 



* A celebrated Dutch philosopher, born in l6'99 at Utrecht, where he became professor of mathe- 

 matics. He afterwards accepted the professorship of natural philosophy at Leyden, and died in 1761. 

 He was author of several works: as, 1. Elements of Physico-Mathematico, 1726; 2. Elements of 

 Physics, 1736; 3. Instituiions of Physics, 174.8 ; 4. Introduction to Natural Phylosophy, ir62. 

 Besides several tracts in the Memoirs of the Paris Academy, for the years 1734, 35, 36', 5i, 56", and 

 60. Also several papers in the Philos. Trans, vols. 33, 37, 38. 



VOL. Vil. P 



