AUG
( 68 )
dition ; with soda it forms an olive green slaggyglass, and with borax a pale yellow semitrans-parent glass. It has been analyzed by Vauquelin,and appears to consist of50. silex24. lime10. magnesia1.5 alumine7. oxyd of iron3. oxyd of manganese
95.5
4.5 loss
To this variety, on the authority of M. Hauy,are also to be referred the Mussite and Alaliteof M. Bonvoisin, of which M. Hauy had onceformed a new species under the name Diopside."
Its colour is greenish or yellowish white: itoccurs crystallized in tetrahedral and dodeca-hedral prisms, or in deeply striated sub-cylin-drical grains, or massive with a lamellar frac-ture. It scarcely scratches glass, and is fusiblebefore the blowpipe into a greyish mass. It iscomposed, according to Laugier , of
» Journ. des Mines, No. 115~.
AUG
57. silex16.5 lime18.25 magnesia
6. oxyds of iron and of manganese
97.752.25 loss.
It occurs in the iron mines of Sudermania;and of Arendahl in Norway .
Var. 2. Sahlite. Malacolite, D'Andrada.
Its colour is pale greyish green; its externallustre is vitreous approaching to waxy; it istranslucent; it scratches glass slightly, but givesno sparks w;th steel, and is easily frangible.Fracture shining and strait lamellar with a triplecleavage. It is generally in the form of coarselygranular distinct concretions, but also occursmassive with a broad lamellar fracture, or crys-tallized in rectangular parallelepipeds slightlybevilled on their lateral edges, or in prisms ter-minated by convex planes. Sp. gr. 3.23.
It is infusible before the blowpipe withoutaddition.
It occurs in Sweden at the silver mines ofSahla ; and at Buoen in Norway .
Its component parts, according to an analysisby Vauquelin, are53. silex20. lime19. magnesia
3. alumine
4 . oxyds of iron and of manganese99.
1. loss.
The Mussite occurs in the Commune ofP>alme-de-Mussa, Department of the Po, in avein accompanied by granular carbonate of lime.
The Alalite occurs near the village of Ala, inthe mountain of Ciarmetta, in a vein accom-panied by garnets.
AUTOMOLITE. Spinelle zincifere, II.
This substance occurs only crystallized. Itsprimitive form is the regular octohedron, be-sides which it presents the transposed octo-hedron. The crystals are for the most part verysmall, rarely equalling in size a small nut. Itsspecific gravity is 4.69 (4.26 Ekeberg). Itscratches quartz. Its colour is a deep bluish-green : the entire crystals are opake, but in thinfragments it is more or less semi-transparent.Its fracture is lamellar, parallel to the faces ofthe crystal, but in other directions is uneven-and scaly with a vitreous lustre.
Before the blowpipe it neither melts nor un-dergoes any change of colour. With phosphate-of soda it runs into a clear colourless bead.
It was first analyzed by Ekeberg, and after-wards by Vauquelin, with the following results..Ekeb. Vauq.
60. — 42. alumine
4. — 4; silex
24. — 28. oxyd of zinc
9. — 5. oxyd of iron
0. — 17. sulphur
0. — 4. portion of the mineral
—— -- remaining unaltered
97. ’ 100,
It occurs at Fahlun in Sweden .
It was at first supposed to be corundummixed with zinc, but the prevailing opinion atpresent is that it is spinelle pleonaste loadedwith blende.
AZOTE WITH OXYGEN, Compoundsof. The specific gravity of azotic gas is tothat of hydrogen, as 13 to l. b 100 cubicalinches of it at a mean temperature and pressure,weigh between 29. and 30. grains.
There are at least three specific compoundsof azote and oxygen ; viz. Nitrous Oxyd, Ni-trous Gas , and Nitrous Acid Gas.k Davy’s Elements.