M. Covelli concludes that this substance has been formed by the action of sulphuretted hydrogen on the sulphate and muriate of copper evolved by these fumeroles; and observes, that its composition accords with such an opinion, the deutoxide being that which forms the Vesuvian cupreous salts.—_Ann. de Chimie_, xxxv. 105. 10. _Fall of the Lake Souwando in Russia_.—This lake, situated in the parish of Sakkola, in the Russian government of Wibourg, and surrounded by the lands of the Barons Friedrichs, was near [p228] 40 versts in length, and had the form of a Γ, or Greek G. Before the year 1818, it was separated from the lake of Ladoga by an interval about a verst in width, called Taipale, on which was a sandy hill; its waters flowed into the river Wuoxa, which united the lakes of Saima and Ladoga. On the 14th May, 1818, the waters of the lake Souwando, increased by the thaw and the tempests, overcame the natural dyke at the foot of the lake, threw down the hill of sand, rapidly flowed into the lower lake, carrying away all the surrounding grounds, and for ever destroyed the barrier which had previously separated them. A chapel and a countryman’s house were carried away with the pastures and meadows; the waters of the lower lake were much disturbed, and the surface covered with ruins. The level of the lake Souwando fell 12-1/2 archines, and its length is now only 15 versts. Its waters no longer flow off by the Wuoxa, but pass into the lower lake by several falls through a deep canal. The land which has been uncovered by the water is already cultivated, and the beauty of the surrounding country said to be increased.—_Bull. Univ._, F. x. 133. 11. _Vegetable Torpor observed in the Roots of the Black Mulberry-tree_.—A very old mulberry-tree was broken into four quarters by the wind in 1790. Two of the quarters were destroyed, the other two remained growing for a few years, but the last of them was removed in 1802. An elder-tree grew in the place of the mulberry-tree, without doubt from berries which had fallen into the middle of the old trunk of the latter. This elder-tree died in 1826, and at the time of its languishing about a dozen of mulberry shoots started forth to the day. M. Dureau de la Malle ascertained that these did not spring from seeds, but from the roots of the old mulberry-tree, which had thus lain in the ground in an apparently inactive state, for 24 years, to send forth shoots at last.—_Ann. de Sciences Nat._ ix. 338. 12. _Method of increasing the Odour of Roses_.—For this purpose, according to the author of the method, a large onion is to be planted by the side of the rose tree in such a manner that it shall touch the foot of the latter. The roses which will be produced will have an odour much stronger and more agreeable than such as have not been thus treated, and the water distilled from these roses is equally superior to that prepared by means of ordinary rose leaves.—_Œkonom. Neuigk._;—_Bull. Univ._