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period on a definite system. There is one special table which calls for notice, that of the daily temperature of the river Weser. The results tend to set at rest the moot question of the relation between water and air temperature. They show that while the water was permanently warmer than the air to the extent of 3° 5 F. on the mean of the year, its changes followed those of the air in point of time, but were less in extent. There are several very suggestive deductions from the tables, and the calendar concludes with some useful practical weather rules.

We mentioned lately that M. Coumbary had organized a Meteorological service in the Turkish empire. He has now begun to publish a monthly résumé of his observations. The provincial stations from which returns for September are published are: Smyrna, Beyrout, Diarbekir, Bagdad, Fao, Rustchuk, Sulina, Varna, Trebizonde, and Salonica. M. Coumbary is very anxious to obtain daily telegraphic reports from Bombay, an idea even more novel than that which is already an accomplished fact, the regular daily service across the Atlantic.

The Bulletin' of the new central observatory at Montsouris, near Paris, has now assumed a definite shape as regards its contents. It gives for the observatory eight readings daily of the various instruments, with reports of the state of the atmosphere and the amount of cloud. Observations are also printed from some stations near Paris, as well as from six stations on the coast, the same as are published in our own 'Daily Weather Report,' and the daily summary of British weather supplied by telegraph to the Ministère de la Marine is appended.

Le Verrier's Atlas Météorologique' for 1868 contains, in addition to the usual charts and accounts of the thunder and hail storms, and a general sketch of the rainfall in France during the year, a number of memoirs of very varied scope. Among them we find one by M. Rayet, on the climate of the Isthmus of Suez; another, by M. Belgrand, on the rainfall in the Seine basin at the Quaternary epoch (this latter might almost as suitably find a place in the Journal of the Geological Society'); and a number of special notices from the various departments. There is, however, a paper by Mr. Buchan, "On the Meteorology of North-west Europe in 1868," which calls for remark. The author is well fitted for the preparation of such a paper by his experience in studying storms; but in our opinion the value of his reasoning is much diminished by the introduction of too much theory. More than once we have a long train of argument depending on a succession of "ifs." This is not logical reasoning at all, and is rather out of place in a paper like that we are discussing. This tendency to theorize we have before had to notice in Mr. Buchan, as a blemish on his work. Let

us have the facts discussed honestly, and few can do that better than he can; but let the theories be kept to be aired before scientific societies and published in their journals. Meteorology has suffered more than most sciences from building castles in the air. Let us lay a firm foundation before we begin the structure.

9. MINERALOGY.

"HERE there is no room for might, could, would, or should,—but it is so; native lead in melaphyre!" With these confident words. Dr. Zerrenner introduces to us the discovery of native lead imbedded in a rock at Stüzerbach, in Thuringia.* And, in truth, his expressions of assurance are by no means ill-timed; for there is confessedly a little scepticism lurking in the minds of many of us as to the genuineness of such a find-scepticism which is perhaps pardonable enough when we remember how often the mineralogist has been bitten by describing old shot and rifle bullets as natural productions! In the case before us, however, there seems no reason to think that Dr. Zerrenner has misplaced his confidencejudging at least from the illustration which shows the globules of lead imbedded in the cavities of the amygdaloidal melaphyre, and more especially from his description which refers to it as running through the rock in strings.

Native lead is also said to have been found, within the last few years, associated with gold in the auriferous drifts of some of the deep mining "leads" in Victoria. Quite recently, too, we have seen some reputed native lead in the form of rounded shot, coated with a whitish incrustation, and accompanied by magnetic iron-ore and native gold, from the old auriferous district in Co. Wicklow.

On a question so obscure and enigmatical as that of the origin of the diamond, every tittle of evidence is worth recording. Dr. Göppert, in his famous essay which gained a prize at the Haarlem Academy in 1864, argued strongly in favour of the formation of this mineral by the wet way. He now publishes an account of certain diamonds containing organic structures tending to confirm his views. Two diamonds in the Royal Mineralogical Museum in Berlin were found to enclose numerous green cells closely resembling those of many algæ. One of the diamonds, weighing 263 milligrammes, contains a very large number of perfectly round

*Berg und Hüttenmännische Zeitung,' No. 12, 1869, p. 105; also, 'Mineralogische Nachrichten,' 1869, p. 33.

The Gold-fields and Mineral Districts of Victoria.' By R. Brough Smyth. Melbourne, 1869. Pp. 420.

Ueber algenartige Einschlüsse in Diamanten, und über Bildung derselben.' Abhandl. d. Schlesisch. Gesellsch. (§ Naturwiss. u. Medicin), 1869, p. 62.

green granules, which appear to be isolated cells not unlike those of Protococcus pluvialis. The new species is accordingly named P. adamantinus. In the second diamond, weighing 345 milligrammes, the cells are less round and more elongated in form, while they frequently unite so as to form a loose parenchymatous tissue: they find their best representatives in Palmogloea macrococca, and Göppert has accordingly ventured to name the new diamond-plant Palmogloeites adamantinus.

Once again, the old mistake has been repeated in Australia. In the New England district a stone was found, about the size and shape of a duck's egg, and weighing 6 oz. 13 dwts. 12 grs. troy. Of course it was taken for a diamond, and rumour was soon rife as to its prodigious worth. A few days after announcing the discovery, the Australian Mail' coolly adds, "The 'great diamond' which had created so much sensation has proved to be a piece of crystal-quartz!"

Hitherto crystallized quartz has been artificially prepared only by wet processes. But the presence of this mineral in rocks usually referred to an igneous origin, naturally leads to the belief that it may certainly be produced also in the dry way. Acting on this belief, Gustav Rose has recently experimented on the fusion of silica, adularia, and other minerals, in salt of phosphorus and in borax. His experiments were conducted on a large scale at the furnaces of the Royal Porcelain Manufactory at Berlin. Crystallized silica was thus obtained, but in the form of small six-sided plates, unlike the crystals of common quartz, from which it also differed in having the low density of 2.3. Rose has thus produced not ordinary quartz, but Vom Rath's curious new species Tridymite, which has been already described in this Journal. Whilst he has thus obtained artificial tridymite, he does not despair of forming artificial quartz by a modification of his process.

Spectrum analysis has been applied, by Vogelsang and Geissler, to the difficult question of determining the chemical nature of the fluid found enclosed in minute quantity in the cavities of certain quartz-crystals.† Fragments of quartz were placed in a small retort, which was connected with an air-pump and exhausted; then by the application of heat the quartz decrepitated, and the evolved vapour was examined in a Geissler-tube. The presence of carbonic acid was thus abundantly proved, and this was confirmed by the turbidity which it produced in lime-water.

Among some minerals examined by Herr Petersen from the St. Wenzel mine, near Wolfach, in Baden, he finds a new species belonging to the interesting group of antimonial sulphides of silver.‡

* Monatsbericht d. k. preussichen Akad. d. Wiss.,' 1869, p. 449.
tRhein Verhdlg.,' xxv. Sitzungsber, p. 77.
Poggendorff's Annalen,' No. 7, 1869, p. 377.

The new mineral is to be called Polyargyrite or Weichglaserz. It occurs in small iron-black crystals, belonging to the cubic system, and consisting of 12 Ag S+ Sb S. Now that we are acquainted with another member of these antimonial sulphides, it may be well to compare the composition and crystalline system of these minerals, since it is hardly probable that another species of this group will be found containing more silver sulphide than is present in polyargyrite.

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Another new mineral from the same locality is described under the name of Wolfachite. It crystallizes in the rhombic system, and contains:-Ni S, + Ni (As, Sb).

English ears will not easily get reconciled to the sound of Wollongongite the name which Professor Silliman proposes for a new native hydrocarbon, which promises to become of great technical importance.* It seems to be a variety of cannel, occurring abundantly in the Wollongong district of the Illawarra coal-field in New South Wales. On distillation it yields a large volume of gas of remarkably high illuminating power.

A mineral mistaken for augite has lately been found by Professor Brush to be a new variety of chrysolite, and he has accordingly named it Hortonolite, in recognition of Mr. Silas Horton's courtesy in calling his attention to it. It occurs in the form of dull blackish rhombic crystals, in the iron mine at Monroe, Orange Co., New York; and from its abundance it may become of some commercial importance as an iron-ore. It is chemically a chrysolite, containing iron, magnesia, and manganese.

Among the fine pebbles of stream-tin from Durango, in Mexico, it is well known that the mineralogist finds the most beautiful little crystals of limpid topaz. With these there have lately been detected certain oblique crystals of an orange-coloured mineral, which Professor Brush names after the locality. The following is the general formula of Durangite, where the protoxides are soda and manganous oxide, whilst the sesquioxides are alumina and ferric oxide: (3 RO) + † (R2 03) As 05. Fluorine is also present in this mineral, but its quantity has not been determined. It is said that Durangite is the only native "fluo-arsenate" which has hitherto been observed.

Professor Brush has also lately published the analysis of a

* Silliman's American Journal of Science,' July, 1869, p. 85.
† Ibid., p. 17.

Ibid., Sept., 1869, p. 179.

meteoric stone which fell near Frankfort, in Franklin Co., Alabama, on the 5th December, 1868.*

The

Attention has again been called to the occurrence of pseudomorphs in Bunter sandstone after scalenohedra of calcite. discoveries of Dr. Blum, already noticed in this Journal, have been supplemented by those of Dr. Klocke, from which it appears that the pseudomorphs occur in several new localities in the neighbourhood of Heidelberg.

A new mica, related to biotite and phlogopite, has been described by Von Kobell under the name of Aspidolite, in allusion to the basal face of the crystals often resembling an oval shield (dois). The crystals are small rhombic prisms, of a dark olive-green colour, and are found in the chlorite of the Zillerthal in Tyrol.‡

So complex is the chemical constitution of that curious mineral, the Tourmaline, that Mr. Ruskin not unaptly calls it "more like a medieval doctor's prescription than the making of a respectable mineral." In spite of its complexity, Rammelsberg has lately succeeded in reducing all his analyses of this substance to the general type of the silicate R. Si Os, where R is considered monatomic, and may represent six atoms of any of the monads hydrogen, potassiumi, sodium, and lithium; or three atoms of the dyads magnesium, calcium, manganese, and oxygen; or two atoms of the triads boron and aluminium.§ All tourmalines fall into two sections one represented by the general formula R, Al, B Si, O1, which is, of course, obtained by doubling the molecule above; whilst the second section contains nine of these molecules written thus:R. Al12 B, Si, 045.

Rammelsberg has also published a chemical note on the constitution of Axinite, and on some native compounds of tantalium and niobium.||

Some good crystals of Gadolonite-the mineral in which yttria was first discovered-have been examined by M. Des Cloiseaux.¶ He finds the crystals from Hitteröe to be doubly refracting, and to contain from 10 to 12 per cent. of glucina; while those from Ytterby are singly refracting, and contain no glucina.

Dr. Sadebeck, of Berlin, whose examination of the crystalline forms of copper-pyrites has already been referred to in this Journal, has lately directed his studies to another common mineral zincblende, and has produced an elaborate paper on the hemihedral forms of this cubic mineral.**

* Silliman's 'American Journal of Science,' Sept., 1869.
Leonhard und Bronn's 'Jahrbuch,' No. 6, 1869, p. 714.
'Sitzungsberichte d. K. bay. Acad. d. Wissenschaften,' 1869.
'Monatsber. d. k. preuss. Ak. d. Wiss.,' 1869, p. 604.

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Zeitschrift d. deutsch, geol. Gesell., No. 3, 1869, pp. 555, 689.
Annales de Chimie et de Physique,' Nov., 1869, p. 305.

Zeit. d. d. geol. Gesell.,' 1869, No. 3, p. 620.

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