410 Progress in Science. (July, 
called electyum. According, then, to this definition, which is still adhered to 
by some mineralogists, the Sutherland gold is an electrum. 
Two specimens of what appeared to be native silver have been analysed by 
Prof. Church, and the results published in the ‘*‘ Chemical News.’ Both came 
from Allemont, in Dauphiny, and were formerly in Heuland’s collection. One 
contained—Silver, 71°69; mercury, 26°15; antimony and traces of arsenic, 
2°16. The other contained—Silver, 73°39; mercury, 18°34; antimony and 
arsenic, 8°27. These figures do not correspond precisely with analyses of any 
native amalgams, nor with the antimonial silvers called dyscrasite, the latter 
being always regarded as non-mercurial. 
Although the Jubilee volume of ‘ Poggendorff’s Annalen,” which has 
recently been issued in commemoration of the fiftieth year of its publication, 
is for the most part devoted to memoirs on the several branches of physical 
science, it is nevertheless of considerable interest to the mineralogist. Prof. 
Rammelsberg gives a masterly sketch of the history of the Chemistry of Minerals 
during the last half century: Vom Rath publishes some valuable crystallo- 
graphic studies; and Hankel gives a resumé of his researches on the pyro- 
electricity of certain minerals. In the same volume Dr. T. Scheerer has a 
paper ‘‘On the Formation of the Minerals which accompany Ores.”’ His in- 
vestigations relate to the conditions under which the most common non- 
metallic minerals of lodes—calc-spar, quartz, barytes, and fluor-spar—have 
been produced. As these may be formed in the wet way, and have probably 
been so formed in nature, it is only rational to conclude that the ores which 
accompany them in mineral veins owe their genesis to similar causes. 
Two kinds of pseudomorphs after rock-salt have been discovered in sinking 
shafts for working some deposits of salt at Westeregeln, near Stassfurt, in 
Prussia. In one case we have a curious example of rock-salt pseudomorphous 
after rock-salt, whose formation may be thus explained: chloride of sodium 
was originally crystallised in cubic forms in a matrix of soft clay; the crystals 
were then dissolved, leaving cubic cavities, which were afterwards more or 
less distorted by movement of the surrounding clay; the walls of the cavities 
were next lined by a thin coating of quartz-crystals; and, finally, the drusy 
cavities became occupied by a second deposit of salt, which thus assumes 
abnormal forms and presents the curious feature of cleavage not necessarily 
parallel to faces of the crystal, since the internal stru€ture bears no relation 
to external form. : 
The other Westeregeln pseudomorphs are six-sided crystals, like those of 
carnallite, but composed almost exclusively of chloride of sodium. Both 
kinds may be found in the same hand-specimen. 
Under the name of Rhagite, Prof. Weisbach has recently described a 
hydrous arsenate of bismuth, discovered among the new uranium ores at 
Schneeberg, in Saxony. The name was suggested by the botryoidal form and 
grape-green colour of the mineral. 
A description of a new Mexican mineral has been communicated by Don 
Ant. del Castillo to the Journal ‘‘ La Naturaleza.”” The mineral is said to be 
a double selenide of bismuth and zinc. 
The name of Huantajayite has been bestowed upon a Peruvian mineral by 
M. Raymondi, of Lima. Its composition seems peculiar; it is said to be 
a double chloride of sodium and silver, containing 89 per cent of the former 
and 11 of the latter salt. It occurs in small colourless cubes, associated with 
the chloride and chloro-bromide of silver and oxychloride of copper. This 
occurrence would seem to show that the metallic chlorides and bromides in 
Peru may owe their origin to the action of sea-water on the minerals of the 
lodes. 
Grochauite is the name which Dr. Websky proposes for a new species 
closely related to clinochlore, occurring in serpentine at Grochau in Silesia. It 
is associated with an ore of chromium described by Dr. Bock as Magno- 
chromite, which appears to be a member of the spinel group, rich in magnesia. 
