428 Chronicles of Science. | July, 
These numbers accord with the formula As Zn? H 6’; while, 
at the same time, the crystalline form shows the most complete 
isomorphism to exist between this new substance and Oliyenite and 
Libethenite. 
Sir David Brewster brought before the Royal Society of Edin- 
burgh a very fine specimen of fossil amber discovered in the kingdom 
of Ava. Mr. T. C. Archer also called the attention of the Society 
to a new bituminous substance imported into Liverpool from Brazil. 
This bituminous shale was submitted to the examination of Dr. 
Edwards, who declared it to contain a larger quantity of oil than the 
Torbanehill mineral. Some specimens of bituminous schists were 
exhibited in the Brazilian collection in 1862; from one of the 
localities then named, this specimen is supposed to be derived. 
In a letter read by M. St. Claire-Deville, at a meeting of the 
Academy of Sciences, M. Wohler described a new mineral from 
Borneo. This mineral, for which the name of Laurite is proposed, 
is a sesquisulphide of Ruthenium combined or mixed with sulphide 
of Osmium. Laurite is found in the form of small globules having 
slight appearance of crystallization. In colour and brilliancy it 
resembles crystallized oligist. An analysis of Laurite gave :— 
Ruthenium : 3 “ P : > orks 
Osmium . : : : 5 ~ oe 
Sulphur. . . . 5 > - 31°79 
This mineral—which appears to be the first example found of a 
natural sulphide of the platinum group—is not attacked by either 
nitro-muriatic acid, or by bisulphate of potash at a red heat. It fuses, 
however, with hydrate of potash and nitre, formimg a brown mass, 
which gives a fine orange-coloured solution. 
M. Berthollet has recently published a new hypothesis on the 
origin of carburets and the combustible minerals.* Although those 
combustible minerals, which obviously result from the trans- 
formation of organic matter, admit of explanation, there are others 
which are not so produced, as the carburets observed in the products 
of voleanic eruptions, and such as have been detected by M. Daubrée 
in meteorites, which require some other explanation. M. Berthollet 
supposes carbonic acid, penetrating the crust of the earth, 1s brought 
in contact with the alkaline metals at a high temperature, that thus 
acetyl is first formed, which undergoes a series of reactions, giving 
rise to the almost infinite series of hydro-carbon compounds. We 
must refer our readers to the original communication and to M. 
Berthollet’s previous experiments. 
M. Pisani in one of the last séances of the Académie des Sciences 
presented a note upon a new mineral, which had been especially 
examined by M. Adam. It is an arseniate of copper, but differmg 
* Sce ‘ L'Iustitut,’ May 16, 1866. 
