horant of. The petrosilex of Sahlberg, not only does not be long to compact felspar, but constitutes a new species, composed of silica, alumina, soda, and magnesia.-Bullet. Univ. Aout 1827. GEOLOGY. 12. From what Countries have the Islands in the West Indies derived their Plants?-M. Moreau de Jonnes, who supposes that the deposits, whether calcareous or volcanic, of the Antilles, have been left dry by the sea at a later period than the great continents, had, in support of this opinion, to inquire into the origin of their vegetable population, and to endeavour to find out by what agents, and from what countries, each of their plants, was transported to them. For this purpose he prepared, during his residence at Martinique, mixtures of earth adapted for vegetation, and in which, he was well assured, there existed no germs of plants. He exposed them with the requisite precautions, and separately, to the action of tempestuous rains, to that of different winds, of birds of passage, and of various currents, and counted, as far as was possible, the number of species which each of these causes produced. He also endeavoured to estimate how far man himself may contribute to this end, by transporting seeds or germs of plants in the water brought from other countries in ships for the use of their crews, among the matters used for packing foreign goods, among wood and fodder, as well as in ballast, and among the hair of animals. The most powerful and constant of the natural agents appears to him to be the great equatorial current of the Atlantic. He found that, in the space of two months, it brought seeds of 150 different species; but all seeds are not capable of being equally transported by all the agents, and to be able to arrive at a given distance in a condition to reproduce their species, they require to possess certain conditions of lightness, mobility, resistance to destruction, difficulty or facility of germination, and others of a like nature. Thus, among the 150 species of seeds brought by the current, there were only twenty-six that germinated. With regard to the action of man, M. de Jonnes thinks it much superior to that of natural agents, and imagines that, in a few centuries, it is capable of entirely changing the relations established by them in a country immediately after its origin.-Hist. de l'Acad. Roy. des Sc. t. vi. p. cxiii. 13. Fossil Skeletons of Guadaloupe.--Cuvier finds that the calcareous mass in which these human skeletons is imbedded, contains land-shells and sea-shells of the same species as those met with in the neighbouring sea and adjacent land; that, therefore, the mass is modern, and the product of some encrusting springs which run towards the place where the skeletons are met with. 14. Organic Remains of the Alluvium and Diluvium of Sussex. In the alluvial and diluvial deposits of Sussex, the remains of animals hitherto discovered are very few, compared with those found in other countries of England. Mr Mantell mentions but two kinds as having been noticed (Geology of Sussex, p. 284.), viz. the elephant and horse. A short time since some labourers, who were employed in deepening the bed of the river Ouse, which flows through a chalk valley by Lewes, and empties itself into the sea at Newhaven, discovered, in a bed of sand beneath the blue alluvial clay that forms the marshy tract called Lewes Levels, the entire skeleton of a deer of a very large size. The horns were quite perfect, and measure 3 feet in height, and 3 feet 2 inches at their greatest width. The antlers had seven points, and resembled in their form those figured by Cuvier of the Canadian deer. The greater part of the skeleton was destroyed by the carelessness of the workmen, and a few bones only preserved. Of these, the tibia measures 14 inches in length, and the ulna 15 inches to the end of the olecranon. The ramus of the lower jaw (imperfect) 11 inches. These remains are in Mr Mantell's collection at Castle Place, Lewes. Still more recently, bones of the deer have been found in the diluvial gravel that forms the low line of cliffs to the west of Brighton, at Copperas Gap near Southwick. These, like all the other bones that have been discovered in this bed, were broken, and promiscuously intermingled with the soil. Two teeth of a species of deer, and portions of several humeri, were identified. Part of the tusk of an elephant was also found with them, and pebbles of granite, in a state of decomposition, Teeth of the Asiatic elephant have been met with in the loam pits at Hove. The Reverend H. Hoper of Pontslade has these interesting remains in his possession.-Phil. Mag. Nov. 1827. 15. Hansteen's projected Journey to Siberia.-Our distinguished correspondent Professor Hansteen of Christiania writes to us as follows: "I am still living in hopes that I shall be able to set out on my journey through Siberia to Ochotz in February or March 1828. Being myself not sufficiently experienced in natural history, I shall be accompanied by a young mineralogist, Keilhau, of this place (Christiania); and Professor Erman of Berlin has offered me the company of his son Dr Erman, and assures me that Baron von Humboldt and Baron von Buch are ready to furnish him with the necessary instructions in geological and geognostical science." 16. Partch's Journey through Transylvania. - Partch of Vienna, an active and acute geologist, was sent by the Austrian government, in 1826, into Transylvania. He remained in that very interesting, but much neglected, part of Europe from April 1826 to February 1827. In defiance of all the difficulties opposed to him in his progress through a country without roads, covered with extensive forests, and affording only the most miserable accommodation to the traveller, he made a full survey of its mines and saline districts, and of the rock formations over great tracts. Boué gave him the use of the geological maps he constructed during his perilous expedition through that country. He is inclined to refer the saliferous sandstone of the middle districts to the tertiary class of rocks. Boué asks, in a communication to us, Is there not, in Transylvania, a saliferous deposite in the Carpathian sandstone, of the same age with the secondary salt formation, or of some of the gypsums of the Alps, and also a more recent deposite connected with that tertiary molasse which is of the same age with the salt in the blue marl of the Appenines and of Sicily? Boué is of opinion that nearly the whole of the molasse takes the place of the blue tertiary marl, which is higher or newer in the series than the Paris coarse marine limestone: still the position of the lower Nagelfluhe along the Alps is dubious. 17. Fossil Remains of Quadrupeds in the Tertiary Rocks of Vienna.-During the course of last summer, there was found in the tertiary sand (above the blue marl with shells), near to the Botanic Garden at Vienna, fragments of the Mastodon angustidens, and also of the Anthracotherium. M. Fitzinger has described and figured them in a pamphlet lately published. An under jaw of the anthracotherium has been found in the lignite or brown coal of Schauerleithen, near Neustadt, in the vicinity of Vienna, which lignite lies in the blue marl. It is also worthy of remark, that such bones are also found in the coarse shelly tertiary limestone, under the blue marl; so that, judging from the bones alone, we would be disposed to consider both as belonging to the same formation,—an opinion which cannot be entertained. 18. Von Buch's Observations and Speculations in regard to the Alps.-Von Buch, during last summer, visited the Bavarian Alps and the Suabian Alps or Jura, and seems disposed to consider the alpine limestone ridge as recent, probably partly Jurassic and partly chalk. The same distinguished geologist read to the Academy of Munich a paper on the Hippurites found at Reichenhall; and, in Poggendorff's Annals for 1827, he has an interesting memoir on the boulders of granite, &c. spread over the Jura and neighbouring countries, in which he maintains they have reached their present situations at the time of the rising from below of the primitive mountains, which he considers newer than the tertiary. It is worthy of notice, that De Luc of Geneva published at the same time (May last) a similar memoir in the Memoirs of the Soc. de Phys. de Geneva, vol. ii. 1827, in which he states, as his opinion, that the Alps were formed after the tertiary rocks, and that the boulders were dispersed by that great rising from below of the land. 19. Boue's Memoir on European Formations, and their probable Origin.-One of the most interesting memoirs lately published, is that whose title we have just given. It appeared in the Journal of Leonhard for July 1827. Unfortunately the promised map has not been published. 20. Dr Boué on Secondary Rocks.-Dr Boué, during a visit to Solothurn, saw, along with Professor Huggy, the shell limestone (muschel kalkstein) forming protuberances under the Jura limestone, and the rauch wacke, or porous magnesian limestone, with cuneiform masses of gypsum. Above these he found the following arrangement:-lias and its marl; the sand of the inferior oolite; then great masses of oolite and compact limestone; a thick bed of contorted, unstratified, rather crystalline, linestone, without shells; and above this, near to Solothurn, an upper Jurassic deposite, with ammonites, encrinites, crocodiles, and tortoises, Dr Boué is of opinion that the Swiss Jura does not contain any Jurassic deposites newer than the coral rag; and further, that the equivalent for the coral rag is nearly wanting in the German Jura. BOTANY.. 21. Signs of Increase, Maturity, and Decay in Trees; by M. Baudrillac.—The qualities of wood depend much on the state of the tree when cut down. It appears from the experiments of M. Hartig upon wood applied as fuel, that trees which have attained maturity without passing into decay, are the best for the production of heat. Thus the value of an elm of 100 years is to that of one of 30 years, as 12 is to 9; that of an ash of 100 years to one of 30 years, as 15 to 11. When the trees begin to decay, their value rapidly diminishes; thus, if an oak of 200 years yields wood worth 15 francs per corde, a tree of the same kind passing to decay yields wood only worth 12 francs. When the wood is used for other purposes, the advantages conferred by a mature and healthy state are still more considerable. The common elm, growing in a forest, and in good earth, acquires its full increase in 150 years; but it will live many ages, even 500 or 600 years. Large forest elms are cut down with advantage when of an age between 100 and 130 years, and then furnish a large quantity of building wood. The duration of the life of the elm depends much upon the soil; in a dry soil it becomes aged, as it were, in forty, fifty, or sixty years. Elms which have been lopped live for a shorter period than the others. Those which grow by the roadside, or in their plantations, may be cut when seventy or eighty years eighty years of age. In general, the increase of hard woods, as the oak and elm, is small at first; it successively augments until the twentieth or twenty-fifth year, is then uniform until the age of sixty to eighty years, after which it, sensibly diminishes. For these and other reasons, it is important that trees should be cut down when they are at their mature state, and not simply when they undergo no fur |