M. de Humboldt stated that he had established at Berlin, at thebottom of the mines of Freyberg in Saxony, at St. Petersburgh,at Casan, at Archangel, at Irkutsk, on the borders of Lake Baikalin Siberia, and at Pekin, magnetic houses in imitation of the mag-netic observatory established at Paris in one of the apartments ofthe Observatoire Royal. Ever since the reign of Peter the Great,the Russian Government has maintained a mission at Pekin,which is renewed every ten years; but there had never been anymen of science attached to this mission until M. Fuss, the bro-ther of the Secretary of the Academy of Sciences of St. Peters-burgh, made a voyage to China last year, and commenced a seriesof meteorological, magnetic, and astronomical observations,which will be continued by M. Kowanko, a young officer of themines, who is to pass ten years at Pekin. M. Fuss, on the 22dApril last, wrote a letter from that city, which has been commu-nicated by M. Kuppfer to M. Arago and M. de Humboldt, andof which the following is the substance: — M. Fuss made magneticobservations in 17 stations during his progress through the celes-tial empire to Pekin; but he was afraid to take any astronomicalmeasures, on account of the jealousy of the Chinese. A tower inmasonry has been constructed at Pekin, surmounted by a tent,as a protection against the inclemency of the atmosphere. Thisobservatory is surrounded by houses; but, happily for magneticexperiments, no iron is used in the Chinese buildings. The crosson the top of the edifice, belonging to the Russian Mission, whichis only a short distance off, serves as a point de mïre for the azi-muthal directions. On the 30th December, 1830, the magneticinclination was found to be 54° 32′; and the declination observedon the 10th January, 1831, at three o’clock in the afternoon, was1° 42′ 57″ West. The longitude of the observatory is about 114°East of Paris; the latitude has been ascertained with precisionto be 39° 54′ 9″. 5. This observation differs only by 5′ from thatmade by Father Hyacinth. The magnetic observations are made at the same hour as in the European observatories above-men-tioned. Barometrical and thermometrical notes are taken fourtimes every day. From the winter solstice to the date of theletter, the maximum height of the barometer was 345.7 lines ofParis; this was at midnight, on the 10th of March, at whichtime a slight shock of an earthquake was felt towards the North;—the minimum was 330.9 lines, difference 14.8 lines. Thehighest temperature during the same period was 25° centigrade,at four o’clock in the afternoon of the 20th April; and the lowest,13°.5 below zero, at six in the morning of the 5th February: themean temperature was 12°.