NaUiral History — Mineralogy. 41 i 
productions which it affords, much important and useful infor- 
mation is to be expected from this newly established and very 
promising association. 
20. Statue of Mtmnon. — Dr Richardson, who accompanied 
Lord Belmore to Egypt, has presented us with a piece of 
the famous Statue of Memnon. The rock is a highly crystalliz« 
ed sandstone or granular quartz, in some parts intermixed with 
red ochre of iron. The same variety is met with in this country, 
and also abounds in the mountains of quartz^rock that extend 
through several districts in India. 
21c Quartz-Rock in North America. — This mountain rock, 
which was first particularly examined in Great Britain by the 
author of the Mineralogy of the Scottish Isles, has been dis- 
covered in vast abundance in America by Humboldt and 
other travellers. In the last number of Silliman’s ‘‘ Journal of 
Science,” it is described as occurring in great beds, associated 
with limestone, clay-slate, mica-slate and gneiss, in the north- 
west part of Massachusets. 
22. Salt Mines of Villiczka.^'^ome mineralogists are of opi- 
nion, that the salt-beds of Villiczka are contained in that forma- 
tion of limestone named Alpine limestone,” The later ob- 
servations of M. Beudant, however, would seem to prove not 
only that the salt formation of Villiczka, but also that of Salz- 
burg, merely rests on this limestone, but in no case is included 
in it, and is covered by a variegated sandstone, 
2S. Geqgnostical situation of Lapis Lazuli. — Mr Mohr has 
ascertained by actual examination, that the lapis lazuli of the 
Lake Baikal occurs along with calcareous spar and silver white 
mica, in a vein which traverses granite. 
24 . — Geognostical Situation of the Blue Copper (f Chessy.’—^ 
This beautiful copper is frequently associated with malachite 
and red iron-ore. It is disseminated in a sandstone forma- 
tion which rests on primitive rocks, and is covered by Jura 
limestone. The sandstone is a compound of grey felspar, grey 
quartz, and silver-white mica, and is sometimes intermixed with 
clay. The sandstone strata alternate with beds of a slate-clay, 
which inclines to clay-slate. These rocks rest on primitive clay- 
slate. The clay-slate contains a large vein of coppeivpyrites, 
