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ditto.

Clafs second.

ROCK CHRYSTAL.

HARDNESS II; SPECIFIC GRAVITY 2,6.

Varieties.

VENUS' HAIR, white transparent chrystal containing red capillary schorl. THETIS' HAIR, ditto with green AVANTURINE, ditto, opaque, sparkling with gold-like particles. PIERRE d'ALLIANCE, transparent quartz with whitish grey granite. APATITES, a silicious pyramidal chrystalization inclosed in a hexagon. FLUOR PRISM from Spain, the case orfluor prism, of a pale violet, like Derbyshire spar; inner pyramid of a pale yellowish green.

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Rock chrystal is chrystalized quartz, generally in groups or druses of hexagonal prisms, ending in a pyramid of six facets, but is also found in other forms, and sometimes amorphous like quartz. It is of various colours, particularly yellow, violet, white, and. rose coloured.

Structure, Properties, &c.

Its texture is laminar. It cracks and loses its transparency as well as colour in the fire, but does not melt per se, although readily with alkalis. The most rare and curious species of the quartz gem that exists out of Rufsia, (for this empire is the richest in that fofsil,) is the avanturine, a stone * Bergman.

whose very existence is doubted by some mineralogists, and its genus unknown to the rest till very lately. Some specimens brought from Cape Gate in Spain, demonstrate that it is a fine opaque quartz, whose little plates or scales from a particular position reflect the light, and appear like scales of golden mica. It is likewise said to be found in Bohemia.

Russia is particularly rich in all the known varieties of quartz and rock chrystal, except the avanturine; but to make up for the want of that curious stone that has so long puzzled naturalists, it pofsesses three species unknown to the rest of the world, viz. Venus' bair, a beautiful transparent white rock chyrstal containing red capillary schorl, lying often in tufts or trefses, like real red hair in an artificial ring. Thetis' bair is the same stone, containing green instead of red capillary schorl, very lately discovered in Siberia; but the author has not as yet seen any specimens of the green, where the schorl is in such fine threads as the red, nor so regularly arranged, although even that is in general lying without order, except in a few choice specimens. A third stone is likewise peculiar to Rusia, and has received, like the two former, a name characteristic of its form and composition, viz. pierre d'alliance, or alliance stone, from its being composed of transparent quartz, and a fine species of light grey granite, like a porphyry, united in án uncommonly regular manner in the finer specimens, as if two distinct stones were glued together by art. A fine opaline rock chrystal

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is likewise employed occasionally for seals, although Tare, under the name of the Siberian opal.

Where found.

Venus' hair at Moursinsk near Catherinebourg; Thetis' hair, pierre d'alliance, in fifsures of the Ural granite ridges; coloured chrystals from the Ural and Altai mountains.

Value.

A ring stone of Venus' or Thetis' hair costs from fifteen to fifty rubles, according to size and regula rity of the hair, or capillary schorl.

To be continued.

OBSERVATIONS ON AGRICULTURE

AND MANUFACTURES.

To the Editor of the Bee.

SIR, I was much struck with the force of the observations, and the justnefs of the conclusions in the two efsays on the Effects of Agriculture and Manufactures, in the Bee, (vol. xii. p. 204 and 242,) but cannot help at the same time thinking, that the ingenious author looks with rather too gloomy an aspect on the flourishing state of manufactures in this kingdom.

It is true that when manufactures are raised to a great pitch of prosperity, and suddenly thrown back by any untoward circumstance, inexpressible evils are felt, not only by the persons actually engaged in them, but also by the inhabitants of the country in general. But when that prosperity is occasioned by a constant demand for the ar

May 15, ticles produced, its cefsation is never so sudden as to produce any material inconvenience; the demand does not slacken all at once, but slowly, and as slowly the manufacturers begin to feel that their businefs is carried beyond its proper level, and to lefsen their operations accordingly.

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There are however many manufactures to which this will not apply, such as are affected by the fashi ons; but as the check that is given to their operations from time to time, happens not to the whole at one period, the inhabitants of the country at large never feel the fhock-the unhappy adventurers are the only sufferers. Manufactures of this nature, it must be allowed, produce great evils in the community, but they are not to be avoided. If the prince of Wales takes it into his head to wear an embroidered vest, the wealthy inhabitants of the country will have embroidered yests also, cost what they may; and there will always be people ready to make them if they can gain half a crown a-day, in place of eighteenpence, even at the risk of starving some time afterwards.

If the operations of commerce are free, some individuals will in every community become very rich; and their demands for manufactures will either be supplied at home or from abroad. If the natural or political situation of the country admit of these articles being produced at home, cheaper than abroad, a number of people sufficient to supply the demand will presently be established in the manufacture of them; if otherwise, property, equivalent in value to these articles, must be exported to pay for them, and

thus feed as many persons abroad, as would have in the former case been fed at home, by that property. Hence I conclude, that in every prosperous state there must be considerable manufactures except such a system as that which you observe produces such excellent effects, in China be adopted. Of many of the consequences of this system I am afraid the Europeans are still ignorant. One of them, and a very deplorable one, is taken notice of by Mr Smith, the extreme poverty of the labouring class of inhabitants; and such I think is the unavoidable consequence of their being excluded from foreign resources, and from leaving the country when these resources fail.

Agriculture cannot be brought forward in Europe but by its fair competition with manufactures. If the natural and political advantages for both are small, the population of a country will be also small. If those for manufactures are increased, and those for agriculture diminished, the former will flourish at home, and the latter, in consequence of the demand, somewhere abroad, and vice versa.

- And I suppose that, though the moral evils attendant on manufactures are to be lamented, the same laws that encourage agriculture and freedom, and in general promote the happiness of the people, will almost always encourage manufactures also.

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