Imatges de pÓgina
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May, 1814, at which I was present, a small pot containing a pale blue colour was dug up, which the exsited personage, by whose command the excavation was made, was so good as to put into my hands. It proved to be a mixture of carbonate of lime with the Alexandrian frit §.

V. Of the ancient Greens.

Baths of Livia is highly ornamented with The ceiling of the chambers called the gilding and paintings; the larger paintings have been removed, but the ground-work and the borders remain. A fragment detached from the borders, which appears of of a deep sea green. The colouring matter the same colour as the ground-work, was examined, proved to be soluble in acids with effervescence; and when precipitated ammonia, giving it the bright blue tint profrom acids, it re-dissolved in solution of duced by oxide of copper There are scthe baths of Titus, and on the fragments veral different shades of green employed in found near the monument of Caius Cestius: different varieties: one, which approached in the vase of mixed colours I found three Verona; another, which was pale grass to olive, was the common green earth of green, had the character of carbonate of copper mixed with chalk; and a third, which of copper mixed with the blue copper frit, was sea green, was a green combination

walls of the baths of Titus were combiAll the greens that I examined on the nations of copper. From the extreme brilliancy of a green which I found in the I suspected that it might contain arsenious vineyard to which I have so often referred, but on submitting it to experiments, it afacid, and be analogous to Scheele's green; forded no iudications of this substance, and

Theophrastus, in speaking of the manu

facture of glass, states as a report that "chulproved to be a pure carbonate of copper. The greeus of copper were well known scribed by Theophrastus and Dioscorides to the Greeks; the most e-teemed is deunder the name of chrysocolla, and is stated by both to be found in metallic veins.

kos" was used to give it a fine colour, and it is extremely probable that the Greeks took cobalt for a species of chalkos. I have examined some Egyptian pastes which are all tinged blue and green with copper; but though I have made experiments on nine different specimens of ancient Greek and Roman transparent blue glass, I have not found copper in any, but cobalt in all of them t.

Vitruvius states, that the ancients had a mode of imitating the Indian blue or indigo, by mixing the powder of the glass called by the Greeks hyalos, with Selinusian

"creta" or annularian "creta," which was white clay or chalk mixed with stained glass; the same practice is likewise referred to by Pliny.

There is much reason for supposing that this stained glass, or hyalos, was tinged with oxide of cobalt; and that these colours were similar to our smalt. I have not found any powdered colour of this kind in the baths of Titus, or in any other Roman ruins; but a blue glass tinged with cobalt is very common in those ruins, which when powdered forms a pale smalt.

I have examined many pastes and glasses that contain oxide of copper; they are all blueish green, or of an opake watery blue, The transparent blue glass vessels which are found with the vases in the tombs in Magua Gracia are tinged with cobalt; and on analyzing different ancient transparent blue glasses which Mr. Millingen was so good as to give me, I found cobalt in all of

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Vitruvius mentions chrysocolla as a native speaks of an artificial chrysocolla made from substance found in copper mines, and Pliny tallic veins, which clay was most probably the clay found in the neighbourhood of meimpregnated with copper. He describes There is every reason to believe, that the it as rendered green by the herb luteum. native chrysocolla was carbonate of copper and that the artificial was clay impregnated with sulphate of copper rendered green by a yellow dye.

Some commentators have supposed that chrysocolla is the same substance as borax, because Pliny has mentioned that a precobalt in the blue glass found in the ruins of Adrian's villa, and at this time I had no idea that cobalt was known to the ancients. Mr. Hatchett and Mr. Klaproth had both found oxide of copper in some ancient blue glasses, which I conceive must have been opaque.

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paration called by this name was used by goldsmiths for soldering gold; but nothing can be more gross than this mistake, which however, has been copied into many elementary books of chemistry. The material used for soldering gold consisted carbonate or oxide of copper mixed with alkaline phosphates. This is evident from the description of Dioscorides" Peri tou skolekos," lib. v. c. 92, who says it was prepared from urine treated in brass mortars. Pliny says likewise, that it was prepared from" Cypria rugine et pueri impubis urina, addito nitrot." The name of chrysocolla was probably derived from the green powder used by the goldsmiths, and which contained carbonate of copper as one of its ingredients.

Vitruvius says that the colour differed according to the country from which the shell-fish was brought; that it afforded a colour deeper and more approaching to violet from the north ra countries, and a redder colour from the southern coasts. He states, that it was prepared by beating the fish with instruments of iron, freeing the purple liquor from the shell containing it, and mixing it with a little honey: and Pliny says, that for the use of the painter argentine,." cretat" was dyed with it: and both Vitruvius and Pliny say, that it was adulterated, or imitations of it made, by tingeing "creta" with madder ‡, and "hysginum." The finest purple, Pliny says, had Amongst the substances found in the a tint like that of a deep-coloured rose: and baths of Titus were some masses of a grass in painting, he states that it was laid on green colour. I at first thought these to give the last lustre to the sandyx, a might be specimens of native chrysocolla; composition made by calcining together they proved indeed to be carbonate of cop-red ochre and sandarach, and which per, but it had formed round longitudinal therefore must have been nearly the same nuclei of red oxide of copper, so that pro- as our crimson. bably these substances had been copper nails or small pieces of copper used in the building, converted by the action of the air, during so many centuries, into oxide and carbonate.

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The ancients, as it appears from Theophrastus, were well acquainted with verdigris. Vitruvius mentions it amongst pigments; and probably many of the ancient greens, which are now carbonate of copper, were originally laid on in the state

of acetite.

The ancients had beautiful deep green glasses, which I find are tinged with oxide of copper; but it does not appear that they used these glasses in a state of powder as pigments.

The greens of the Aldobrandini picture are all of copper, as was evident from the action of the muriatic acid upon them.

VI. Of the Purple of the Ancients. The Porphyra of the Greeks, and the ostrum of the Romans, was regarded as their

most beautiful colour, and was prepared from shell-fish.

Hist. de la Peinture ancienne, pag. 38. "Nos droguistes la nomme Borax."

† Lib. xxxiii. cap. 5.

In the baths of Titus there is a broken vase of earthenware, which contains a pale rose colour; where it has been exposed to air, it has lost its tint, and is become of a cream colour, but the interior has a lustre approaching to that of carmine.

I have made many experiments on this colour. It is destroyed, and becomes of a red brown by the action of concentrated acids and alkalies; but diluted acids dissolve a considerable quantity of carbonate of lime with which the body colour is mixed, and leave a mixture of a bright rose colour: this substance when heated first blackens, and when urged with a strong flame becomes white; and treated with alkali, proves to be composed of siliceous, aluminous, and calcareous earths, with no sensible quantity of any metallic substance, except oxide of iron.

* Lib. vii. cap. 13.

+ Probably a clay used for polishing silver. The ancients were not acquainted with the distinction between aluminous and calcareous earths, and creta was a term applied to every white fine earthy powder.

Madder was extensively used by the ancients in dyeing, and from this passage it is probable that they were acquainted with the art of making a lake from it similar to that used by modern painters. It was probably one of the colours used by the Egyptians in dyeing their stuffs of dif

The commentators have been likewise misled by Pliny's description "Chrysocolla humor est in puteis per venam auri defluens," &c. Ibid; but this is merely an inaccurate account of the decomposition of a vein containing copper. We have no reason for supposing that the Greeks and Romans were acquainted with borax.ferent colours from the same liquor, by Pliny, probably misled by the application means of mordants. If we can trust Pliny's of the same name to different substances, account, they practised calico-printing in a considered chrysocolla as the cement of manner similar to the moderns. Lib. XXXV. gold in mineral veins, cap. 42.

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I endeavoured to discover if the colouring matter was combustible. It was gradually heated in a glass tube filled with oxygen; it did not inflame, but became red hot sooner than it would have done had it been merely earthy matter: on exposing the gas in the tube to lime-water, there was a precipitation of carbonate of lime. Some of it was mixed with hyperoxymuriate of potassa, and heated in a small retort when the salt fused there was a light scintillation, a little moisture appeared, and the gas given off received into lime-water occasioned a very evident precipitation.

which in the case of so small a quantity of matter diffused over so large a quantity of surface could not have afforded unequivocal results.

The durability of this lake, whether vegetable or animal, is a very curious circumstance; but the exterior part which has been exposed to air has suffered. This durability probably depends in a great measure upon the attractive powers of so large a mass of alumina; for, whenever one proportion of a substance is combined with many proportions of another substance, it is very difficult to decompose or detach the one proportion.

It appeared from these experiments, that the colouring matter was a compound of either vegetable or animal origin. I threw some of it upon a hot iron: it emitted scarcely any smoke, and gave a smell which had some resemblance to that of Prussic acid, but which was extremely faint.

From the circumstances which have been noticed respecting this colour, it is impossible to form an opinion whether it is of vegetable or animal origin. If of animal origin, it is most probably the Tyrian or marine purple: and by some comparative experiments on the purple obtained from shell-fish, the question might perhaps be decided. It is very probable that the most expensive colour would be employed for ornamenting the imperial baths; and it is not impossible that Pliny may have al

When hydrate of potassa was fused in contact with it, the vapours that rose had no distinct ammoniacal smell; they gave indeed slight fumes to paper moistened with muriatic acid, but this is far from being an unequivocal proof of animal matter.luded to the palace of the Casars when he says "nunc et purpuris in parietes migran tibus, et India conferente fluminum suorum limum, et draconum et elephantorum sanjem, nulla nobilis pictura est." Lib. xxxv. cap. 32.

I compared this colour with vegetable lake from madder, and animal lake from cochineal diluted to the same degree, as near as possible, and fixed upon clays. The lake of maider, after being dissolved in strong muriatic acid, had its colour restored by alkalies, which was not the case with the ancient lake. The lake of madder likewise gave a much deeper tint to muriatic acid, and produced a tawny hue when its weak muriatic solution was acted on by muriate of iron; whereas the ancient lake did not change in colour. The ancient lake agreed with the lake of cochineal in being dered of a deeper hue by weak alkalies, and of a brighter hue by weak acids; but it differed from it in being much more easily destroved by strong acids. It agreed with both the vegetable and animal lakes in being immediately destroyed by a solution of chlorine.

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I have seen no colour of the same tint as this ancient lake in any of the ancient paintings in fresco. The purplish reds in the baths of Titus are mixtures of red ochres and the blues of copper-In the Aldobrandini picture there is a purple in the garment of the Fronuba, but of an inferior hue; and this purple appears to be a comren-pound mineral colour of the nature of these.

It was not destroyed by solution of chlorine; and when a little of it was exposed to muriatic acid, it rendered the acid yellow, and the remainder yielded a residual blue powder.

(To be continued.)

M. Chaptal considers the lake he found amongst the colours from Pompeii (as I have already mentioned) as of vegetable origin; and he founds his opinion upon the circumstance of its not affording by decomposition the smell peculiar to animal substances: but probably this smell, even if produced by recent purple colouring matter of animal origin, would not belong to colouring matter of 1700 years old. For it is most probably owing merely to albumen or gelatine not essential to the

The lake made from cochineal produced much denser fumes when exposed to fused potash, and afforded a distinct ammoniacal smell. The two modern lakes when burnt in oxygen, did not give stronger signs of inflammation than the ancient. I ascertained the loss of weight this ancient lake suffered by combustion, and found it only one-thirtieth, and this loss must in great part have depended on the expulsion of water from the clay on which it was fixed. This circumstance induced me to renounce the idea of attempting to determine its na-colouring particles, and much more pature from the products of its decomposition; pidly decomposed.

The Gatherer.

NO. VIII. NEW SERIES.

"I am but a Gatherer, and Dealer in other Men's Stuff."

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fifty roubles, at 1s. 2d. each, or 2l. 18s. 4d Changing a window from bladders to glass, cost 12s. each. Such a cottage as lets in Suffolk for two guineas a year, might have been built at the same time, in the manner of the country, for 100 roubles, or 5l. 16s. 8d. To change the roof of this cottage for one of tiles, would cost eighty roubles. A house built of stone and tiles, of three rooms, was bought for seventy-five roubles; but building it, would have cost 300 roubles, or 17. 106. A square Russian fathom, being seven English feet of stone walling, for a house or fence wall twenty one inches thick, costs, (mortar, mason, and carriage included,) twelve roubles; a cubical fathom of stone for building laid down on the spot, costs five roubles; and to work these stones into a wall, the mason and mortar comes to seven roubles more per square fathom, twenty one inches thick. A sawn plauk in the merchant's yard, twenty one feet long, fifteen inches broad, and two inches thick, is bought for two roubles and a half: yet these planks are brought 1500 miles-Furniture. Price of a bedstead ten roubles, a mattrass twenty five roubles, a cotton coverlit fifteen roubles roubles-Live Stock, Price of a farm horse a common chair two roubles, a table five 31. 10s. a riding ditto 44. 15s. 4d. a pair of large plough oxen 71. 16s. a cow with a calf by her side 24, 78, a ewe and lamb 11s. 8d. a sow fifteen roubles, cocks and hens half a rouble each, turkeys one rouble and a half, geese three quarters of a rouble, plough harness for two oxen five roubles— Implements. A plough for going ten inches deep, with irors, twenty five roubles; a common German plough for four oxen, that goes five or six inches deep, seventy or eighty roubles, a common ox-cart of the country, noiron, twenty roubles-Labour, Common day labour, in summer, one rouble and a quarter; ditto. in winter, three quarters of a rouble; alad for keeping cows and sheep, wages seventy roubles a year, and to be fed; a maid servant, being a good working girl, wages ten roubles a month, and food; a common ditto, five or six roubles per month.-Fuel. Expence of one fire, to buy the wood, thirty roubles per ann. Every body makes their own candles.-Provisions. Game of all kinds, and wild fowl, in the utmost profusion; a one horse cart load of sea fish 11s. 6d. very fine oysters 11s. 6d. per 1000; Anchovies 91b. for 24d. the finest Greek wines 17d. per bottle. From these particulars it is sufficiently evident, that a family may settle in a most fertile and entirely level pasture, free from wood and stones, and capable of being ploughed without the

REV. ARTHUR YOUNG'S PROPOSED EXCURSION TO THE CRIMEA. Cælum non animam mutant qui trans mare currunt.

In page 469 of the present Volume, the Gatherer has recorded the proposals of a patriot who wishes to disburden his country of a part of its superfluous population. He has now the satisfaction of announcing further particulars. The low price of Every thing will certainly tempt those who wish to sell cheap as for instance, good horses at about four guineas, and good wheat at about three shillings and sixpence :-those who wish to make their per bushel: own candles; those who wish to live retired, not interupted by comers and goers, or other pests of society. Society!-it is not known: Information on public affairs, -none!—on private affairs,-none! Markets in the neighbourhood, none! Religion and Public worship-Morals,—Literature &c. &c. none-none-none.

The

Plague-only now and then. Now for furtherpar ticulars :--which we copy verbatim.

The Proprietor of an Estate in the Crimea, to which he was going in July 1815, is obliged to postpone his journey till the spring of 1816: his advertisements have brought so many applications, that he feels it to be necessary, in order to answer their many enquiries, to print the following statements:-The expence of the journey by sea and land, on a rough estimate, may be reckoned at from 16. to 201. each person, with economy, if the number be small; less for large families.-Building The expence of building a small English Cottage of two rooms, the walls wattled, and pastered in the manner of the country, with a mixture of cow-dung, and the roof covered also in the method of the country, one chimney, bladder windows, was built in 1813, all expences included, for

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there was not the least symptom of decay, 400 The rings in its butt were carefully reckon-aned, and amounted to above 400 in nun, it is ber, a convincing proof that this tree was of in an improving state for upwards of 400 years; and as the ends of some of its bran--ches were decayed and had dropt off, it is presumed it had stood a great number of years, after it had attained maturity.

BIME.

INSTANCE OF THE PROGRESS OF CRIME. by
To the Editor of the Literary Panorama.
SIR,

*%10
In

smallest previous expence, on a capital surprisingly small. The people of the country plough and sow wheat for the first crop without any enclosure; but when the cora is coming into ear, it is watched, to keep off the horses, cattle and sheep, which graze upon the estate. The price of the land to a purchaser, in lots of not less than 100 acres, will be, according to situation, from 1 to 21. per acre, and rent in general about 1s. per acre. The price of wheat at present is 3s. 6d. per bushel. The Es tate is within eleven miles of Caffa, an exporting sea-port within three days' sail of Constantinople; a cousiderable trade from Caffa to Malta in corn and salt beef. The Crimea is the only province of Russia in which a purchaser of land does not become a Russian subject. No taxes whatever; no tithes; no poor rates. All Foreign settlers are under the protection of the Em-lightly of, the practice of poaching. Per- e. aperor. As the rouble, at par, is 2s. 6d. haps there are few means of benefitting the be every pound sterling in gold or silver in-public more essentially, than by the pre-macy. creases as two and a half to one, on being vention of crime; and this cannot be bet-val carried to Russia; 1007. becomes near 300/ ter accomplished than by exposing the na352 at the present rate of Exchange, the rouble tural progress of that course which be- fi in 1815 being only 101. Price of the whole gins in secrecy, is continued in obstinacy, or s estate, paid in England, 5,000l. and from transgressions apparently trivial, gradually hardens the sinner, till his life becomes a burden on Society, and he falls a sacrifice to the law. Imaginary Histories tracing this progress are liable to exceptions from various causes; but real his

In your last number, you were led by the the benevolence that marks your work, to very notice particularly, Mr. Chaplin's Sermon Pr at Bishop's Stortford, respecting the execu- the tion of criminals who had begun their precareer of crime by what some think very bat

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THE GOLENOS OAK.

Description of the Golenos Oak, purchased by the late Thomas Harrison, many years his Majesty's purveyor of Ply-tories not only make a powerful impression mouth dock-yard and Dean Forest, and on the immediate neighbourhood where felled and couverted by him in the year the culprits are known, but ustially 1810:-It grew about four miles from the wherever their truth can be substantiated. town of Newport, in Monmouthshirethe main trunk at 10 feet long, produced 450 cubic feet; one limb 355, one ditto 47%, one ditto 113, and six other limbs of inferior size averaged 93 feet each, making the whole number 2,426 cubic feet of convertible timber. The bark was estimated at six tons, but as some of the very heavy body bark was stolen out of the barge at Newport, the exact weight is not known. Five men were twenty days stripping and cutting down this tree; and a pair of sawyers were five months converting it, without losing a day (Sundays excepted.) The money paid for converting only, independent of the expences of carriage, was £82; and the whole produce of the tree when brought to market was within a trifle of £600. It was bought standing for £450; the main trunk was 9 feet in diameter, and in sawing it through, a stone was discovered six feet from the ground, above a yard in the body of the tree, through which the saw cut; the stone was about six inches in diameter, and completely shut in, but round, which

VOL. II. Lit. Pan. New Series, August 1.

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I have, therefore, thought that your laudable intentions might be promoted by the communication of the following unquestionable narrative of facts, which have lately occurred in this county. It may deter some not yet hardened in guilt; or it may warn those to whom the way of transgressors presents temptations. How much happier is the honest man, though poor! How much more truly his own master, than these slaves to bad habits, who refus ing to obey restraints neither harsh nor burdensome, treat them with contempt, till at last, crime follows crime, and what they would not have believed it possible they should be guilty of, at first, becomes not merely tolerable, but even familiar and ordinary. They live in, and by, the very guilt which they abhorred they end hy depriving others of life, and thereby fore fe feiting their own.

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If the misery and distress fell only on of themselves, the misfortune would be less than it is; but we have reason to fear that others, also, innocent men, not seldom suffer from the wickedness of such 2 F

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