An Account of an Earthquake Felt in Holland, Feb. 18, 1756; In a Letter from Mons. Allemand, Professor of Natural Philosophy at Leyden, and F. R. S. to Mr. Trembley, F. R. S. Dated at Leyden, Feb. 27, 1756. Translated from the French

received five successive shakes. The sconces in the chamber were in like manner moved. Ten or twelve minutes after, I perceived a second shock, but not so strong as the former. The water, which I looked upon, remained quiet. The air was calm. There was a little fog. The Wind was S.W. Immediately after the earthquake, it turned N.E. The news from Maestricht and Utrecht brings word, that they have likewise felt it there. LXXVII. An Account of an Earthquake felt in Holland, Feb. 18, 1756; in a Letter from Mons. Allemand, Professor of Natural Philosophy at Leyden, and F.R.S. to Mr. Trembley, F.R.S. Dated at Leyden, Feb. 27, 1756. Translated from the French. Read March 4, 1756. There was felt here a violent shock of an earthquake on the 18th of this month of February, three or four minutes before eight in the morning. It was not perceived in my house, nor in many others: but those persons, who were in bed, or not in motion, felt it. Two of the bells in this city struck each one stroke. A considerable number of people were affected with a kind of vertigo, without being sensible of the earthquake. It was felt throughout the whole territories of this republic. It occasioned much confusion at Amsterdam in some churches, where service was performing. Many persons quitted their houses at Maestricht; but only for a short time. Since the first first shock on the eighteenth, at eight in the morning, which threw down some chimnies, several others have been felt in that city. LXXIX. An Account of the Earthquakes felt at Brussels; in a Letter from John Pringle, M.D. F.R.S. to Thomas Birch, D.D. F.R.S. Read Mar. 11 1756. BY a letter, which I received a few days ago, from Dr. Brady, physician to the court at Brussels, I find they have felt in that city this winter three several shocks of an earthquake. The first was on the 26th of December; the second on the day following; and the third on the 18th of February; being the same day it was said to be felt on our coast, between Margate and Dover; but the hour is not mentioned. All these shocks, he says, greatly alarmed the inhabitants; but were otherwise attended with no bad consequences. Dr. Brady adds, that he was told by a gentleman from Liege, that the men, who were at work in the coal-pits, and particularly in some of the deepest, near that city, had assured him, that they heard the rumbling noise preceding the shock as over their heads; whilst those, who were above ground, heard the same kind of noise as under their feet. I have inclosed a letter, which, if you think proper, may be laid before the Society, as containing an