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"XXXIII. Account of fome Roman Pottery, found at Sandy in * Bedfordshire, and at Lincoln, together with a Roman Speculum.

By Governor Pownall.' ? Pottery of this very fabrique,' fays the governor in his affectedly Frenchified language, with exactly similar mould<ings and ornaments, is at this day found in Provence and

Languedoc, particularly at Aix and Nismes ; at Vienne in • Dauphine; and in many parts of France; as alfo in many

parts of Switzerland.'~. This fabrique was usually called the . Samian, mentioned by Pliny, xxxv. 46.'-There is as much « difference, betwixt the composition of this fabrique and the "home-made pottery of ancient Europe, the grey, black, and

brick-red pottery found every where; as between the porce(laine of China, and the common fuyance of Europe.' . - In Chester Field at Sandy was dug up, some years ago, an urn containing bones and ashes, &c." There was in it a hair

pin of that fort, called the hafta recurva. This is now loft. . But there still remains a curious mirrour or speculum, which

I believe, you will find to be of a mixt metal, copper, « silver, and iron. It is surprising, that it has preserved its po«lilh to so great a degree, after lying buried fo many hundred 6 years.'

XXXIV. Description of the Druid Temple lately discovered on ! the Top of the Hill near St. Hillary in fersey. Communicated by Mr. Molesworth.' XXXV. Description of a Druidical Monument in the island of

Fersey; in a Letter from the Right Hon. H. S. Conway, Go ... vernor of Persey.'

We have here a double account, three views, and one ground-plan, of a monument in Jersey, which the writers of both these eflays denominate a Temple, " The present temple, says the general, remained entirely covered with earth till the • fummer 1785; having the appearance of a large barrow or tumulus, in which form I had constantly feen it when in the

island. It then happened, that the colonel of the St. Helier's ( militia wanting to level the ground for the exercise of his

corps, the workmen soon struck on the stones, and the temple thus discovered was afterwards cleared as it now flands. There

is no trace of the time, when it was covered up; not impro<bably in that of the Romans, by the Druids themselves; to pres ferve it, as their most sacred temple, from the violence of profanation of that people, who frequently persecuted them,

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? and who certainly had possession of the island. But we beg leave to inform this respectable officer and scholar, that a temple covered up by Britons to conceal it from the Romans; profaned by those, to prevent it being profaned by these ; and profaned by men, who used it as a temple, to save it from being profaned by men, who confidered it only as a rude circle of stones; is such a folecism in antiquarian fpeculation, as refutes itself sufficiently, It is historically false too; as the hundreds of British temples in our own islands, never covered up from the eyes and hands of the Romans; and particularly those grand cathedrals of the Druids, the temples of Abury and Stonehenge, boldly looking the Romans in the face, and defying their profanest touch ; demonstrate to our very senses. And the fact is, that this imaginary temple is nothing more than a BARROW. Such it appears in the views here given. Such the General had always considered it; it hav• ing', he says, the appearance of a large barrow or tuniulus, ! in which form I had constantly seen it when in the island.' It only differs from other barrows, in being a circle instead of a cromlech of large stones, at the base. This forms an ampler chamber for fepulture within; which is very observably divided into cells like those of a Cromlech, for the burying-places of distinct persons; but has one cell directly opposite to the entrance, and conspicuously larger than the rest. All shews the barrow to have been constructed for some considerable personage, the Sovereign of the island probably, and for his family. These were to be successively buried here, in their several cells or fromlechs; the earth being accumulated upon each cell, as it was filled. And, what fixes the whole to be a sepulchre at once, there is a secret passage to it formed of side and covering stones, about four feet in height, and narrowing as it approaches the chamber; a road of access, for the interment of some more diftant branches of royalty, in the earth already accumulated within. The supposed entrance in it,' says the anonymous author, may be called a subterraneous passage, and measures « fifteen feet in length;-the inside of the passage measures five < feet three inches in breadth, four feet four inches in height, and ! the first covering stone three feet in thickness.' Thus do we sweep away an imaginary temple, and substitute a charnel-house in the room of it. Nor was it constructed at the first reduction of northern Gaul by the Romans. It was the work of a later period, when the Romans had been for a century masters of the island. "Two medals were found in this temple,' says the former essayist, - one of the Emperor Claudius, and the other so

worn by time as to render it unintelligible.'. The outside of the entrance too is guarded by apparent cromlechs; the tonibftones of inferior persons, attendant on the royal chamber of

repose.. repose. Also about fifty yards south from the temple, are five

places in the form of our graves, masoned on every side, but s not paved, and lying east and west.' And, as Mr. Fall, in his history of Jersey, mentions a fingle altar of large dimensions then standing on the same bill of St. Helier,' by which in all probability he means merely a cromlech,' and near it a circle of

other ftones, of which there remained but one when he wrote, o the rest huving been bicken to make a wall hard by ;' so this concurs with all, to prove the present building no temple, but a fepulchre, and a sepulchre placed adjoining to a temple,

ART. VII. ' A Comparative View of the Phlogistic and Antiphlo

gistic Theories ; with Inductions. "To which is annexed an 'Anadysis of the Human Calculus, with Observations on its Origin, &c. By William Higgins, of Pembroke College, Oxford. 8vo. 6s. boards, Murray. London, 1789.

THE late splendid discoveries in chemistry, while they have

enlarged our knowledge of the subject, have given birth to two opposite systems. The philosophers on the continent, at the head of whom is M. Lavoisier, have produced a theory which furnisħes easy, clear, consistent, and elegant explanations of the various phenomena. At the same time, they do not propose it as absolutely complete; they introduce alterations or im- ' provements according as the progress of discovery suggests. The adherents of the ancient system labour hard to support the mouldering fabric. Many important points have been given up, many have been adopted, the theory has been variously moulded, and now little seems to be retained but the name. Mr. Higgins enters the lists with the ardour of a youthful champion. His views are fanguine, his ideas bold and ingenious. He has collected facts that are numerous and important, he has added several new experiments to the general stock, and has contrasted the different merits of the opposite systems with success. His assertions indeed are often bold, and his arrangement sometimes obscure; but the warmth of novelty, and the controversial na, ture of the subject, form a sufficient apology. '. · Mr. Higgins's experiments serve to disprove the conclusion drawn by Dr. Priestley from the inflammation of the oxygenous and hydrogenous gases. The minute portion of acid is merely adventitious, and water is the real product. Vitriolic acid contains no carbonic gas as its acidifying principle ; it consists of oxygenous and fulphureous acid; for pure alum, heated to ignition, yields these products. If iron be dissolved in concentrated pitriolic acid, it absorbs the oxygen and renders it volatile. If

the

the acid be diluted, the water is decomposed, and the hydrogenous gas is given out. When steam is passed over fused tulphur, the oxygen unites with the fulphur, and forms vitriolic acid, while the hydrogenous gas is extricated. Mr. Higgins thus ftates the effects of oils upon vitriolic acid: - - Vitriolic acid, poured in fmall proportion on a large quantity of oil, will turn it to a darkish brown colour. This expofed to heat will yield fixable air and volatile vitriolic acid, with a small quantity of phlogisticated and heavy inflammable air; and, if the charge be urged with a tolerable strong heat, a small quantity of fulphur may be produced. Hence we may infer, that the acid is only deprived of a portion of its dephlogisticated air. Animal and vegetable inflammable bodies have certainly stronger affinity to dephlogisticated air than iron has, though they will not readily unite under any circumftance below the temperature of ignition. Oils, animal or vegetable, provided they be free from volatile alkali, will not mix or unite with water in a common temperature, but when diffused with it by agitation will assume a globular figure, and instantly separate from it again on ftanding: here, the repulfive force between oil and water is evi. dent. If oil and water be boiled under the common pressure of the atmosphere, no decomposition will take place; but of water be gra. dually dropped into boiling hot oil, inflammable air will be produced, as has been firii observed by Mr. Lavoisier. The joint action of air and water can have no great effect on there, and if any at all, it must be in a great length of time. Suet and butter are not decomposed by water alone; for I can affirm that I have been present when a small tub of butter had been taken from under ground at least three feet deep, and which, from the situation of the soil and the decay of the wood, must have sain there for upwards of fifty years. It was surrounded with water, for it lay in a marshy soil. It had a disagreeable tafte, and a spongy white appearance, but did not feem much changed in its chemical properties.'

M. Gengembre fhewed that hepatic gas was hydrogenous gas in which sulphur is fulpended. Dr. Austin has confirmed this theory by several ingenious experiments. He precipitated the fulphur by passing an electric spark repeatedly through hepatic gas. He fused sulphur in hydrogenous gas, azotic gas, and heavy (infaminable air,' or a mixture of hydrogenous and azotic gases. The two former were not in the least altered, but the latter afforded { its original bulk of hepatic gas. Mr. Higgins combined hepatic gas with the oxvgenous, and found the refi. duum was sulphureous acid.--Mr. Kirwan's theory of nitrous acid is clumsy and complicated. The hypothesis of the acidifya ing principle derived from the carbonic gas is inconfiftent with the experiments of Mr. Higgins and Mr. Cavendish. That carbonic gas is composed of charcoal and oxygen, and that nitrous acid is formed from oxygenous and azotic gases, is confirmed by the following experiment of Mr. Higgins ;

: I fused ... I fused a quantity of nitre in a small earthen tubulated retort; whose neck was elongated with a glass tube which immerged in water and introduced into it 10,33 gr. of red-hot charcoal, which was exposed to a Itrong heat for half an hour. It was a whole piece, and the weight was ascertained as soon as it was taken out of the fire. When it got in contact with the fused nitre, a rapid deflagration enfued, attended with a copious extrication of fixable air. When I obtained about 40 cubic inches of air the deflagration ceased, and the charcoal was about confumed. The fixable air was very pure, conraining but 7 cubic inches of phlogifticated air. The difficulty of separating the alkali from the residuary charcoal without waste, and the impoflibility of consuming the entire of a quantity of charcoal, as it must be used whole in this experiment, render it impracticable to exactly ascertain the quantity of fixable air a given quantity of chatcoal would yield; for, as soon as the nitre next the charcoal is de. composed, the process ceases. In order to obviate this inconveniency as much as possible, I introduced a long and flat piece of charcoal, weighing 10 grains, into a fresh charge of nitre; and, as soon as the deflagration commenced, I kept the charge in continual agitation; which, with the large surface the charcoal itself exposed, enabled me to nearly consume the whole. The quantity of charcoal lefs could not exceed 2 grains. I obtained 80 cubic inches of air, 67 of which were fixed air, and the remainder phlogisticated air.'

Mr. Higgins introduced some iron filings, recently prepared, into pale nitrous acid largely diluted ; the metal robbed the acid of its oxygen; and azotic gas alone was produced. Equal parts of hepatic and nitrous gas, when mixed, contract to of their bulk, and deposit sulphur. Red nitrous acid, exposed to oxygen gas, gradually absorbs it, and becomes colourless. The astonishing effects of the effusion of oils upon nitrous acid is well known; but even charcoal, if it be very dry, can be inflamed by nitrous acid.

The nature of the marine acid is the least known. It is probable, both from experiment and analogy, that it consists of a certain bafis united to oxygen. But such is the volatility of the acid, and so strong its attraction for oxygen, that its bafis has never been separately exhibited. If common salt and litharge be: fused, the acid unites to the lead without suffering decompofition. Common salt mixed with clay, and exposed to a fierce heat, is in part alkalised, but afterwards it becomes neutral by exposure to the air. Mr. Higgins infers the composition of the marine acid from its calcining the metals, and combats with great fuccess the opinion of some phlogistians that water unites to form calces. Unlike the other acids, the marine becomes more volatile from the excess of oxygen; and hence the dephlogisticated muriated acid of Schee!. If this oxygenated acid be exposed to the light of the sun, it will yield oxygenous gas; and hence it

can

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