FOREIGN CORRESPONDENCE. 



259 



There is a slight error in the figures on the right, representing 

 ohgoclase and angite. 



During our visit to England, in the autumn of last year, M. Prost 

 published the following note (which has escaped our attention until 

 now) upon certain vibrations of the earth observed at Nice during the 

 winter of 1857-1858, and since that period: — "When I came back 

 to Nice in October, 1857, my pendulum remained perfectly quiet for 

 about twenty days ; but it began to move suddenly on the 4th Nov., 

 and oscillated with considerable intensity. The movement was accom- 

 panied, as usual, by that of tlie glass hangers of the chandeliers. 

 These oscillations, after having diminished gradually for some days, 

 showed a new activity about the 18th, which lasted till the 22d. 

 I have been able to ascertain that the date of the 4th November 

 corresponds to that of the violent earthquake which took place at 

 Meneggio on the Lake of Como, and the other dates with shocks 

 observed on the 19th at Pontevedra and at Lisbon, and on the 21st 

 at Lisbon and Porto. Since then the oscillations of my pendulum have 

 been almost permanent, j^resenting very rare intervals of repose ; and 

 their intensity augmented again on the 15tli December, and lasted 

 for a very long time ; the glass hangers oscillated without interruption 

 up to the first days of January, 1858. It was during this period that 

 the earthquake, at St. Denis-du-Sig, in the province of Oran, took 

 place, on the 14th December ; then the terrible shocks felt at Naples 

 and in La Pouille on the night of the IGth and 17tli December, which, 

 after having been felt on the 17th at Hernosand, in Sweden, on the 

 20th at Agram, in Croatia, continued for a long time, and occasioned 

 many disasters in those countries. Again, on the 25th, shocks were 

 felt at St. Veit, in Austria, and at Adinont and Rosegy in the valley 

 of Eros. Their sphere of activity spread itself, therefore, to a great 

 distance, for during the same period, i. e. from the 20th December, 

 shocks of earthquake happened in succession at Brousse, up to about 

 the 15th of January, and on that day were felt at Ratibor, in Silesia, 

 whilst on the 11th an earthquake took place at Martinique, and on 

 the 26th there was one at Parma." 



About the end of February, 1858, the oscillations of M. Prost 's 

 pendulum began to diminish gradually ; in the months of May and 

 June there were very few. But they began again in July, and con- 

 tinued with increasing intensity until the night of the 4th and 5th 

 August, when a shock took place about half-past two a.m., which 

 awoke the inhabitants of Nice out of their sleep. It is, therefore, 

 certain," says M. Prost, in conclusion, " that this phenomenon of 

 oscillation, which had never yet been observed, is in connexion with 

 earthquakes ; but that it differs from the latter inasmuch as, instead 

 of being sudden and violent, like a shock, it manifests itself as a 

 vibration, the duration of which may be hours, weeks, or even 

 whole months." 



Our accomplished friend, M. Pisani, has lately received from Con- 

 stantinople samples of a new mineral found in the interior of Turkey, 

 and which presents a rather remarkable composition. It is seen to 



