« PreviousContinue »
and 10 feet in autumn 1758, pays above 18 per cent. Besides it should be 184 considered, though he measured the largest and most thriving oak and Scotch fir in 1743, yet several others of the same age, both oaks ahd Scotch firs, have greatly exceeded the measured trees for many years past; e. g. the oak 'No 11, appears by the table 2 feet 8 inches 2-8ths in circumference; and another just by it is 2 feet 11 inches 6-8ths; and an oak transplanted from this grove, is 3 feet 9 inches 5-8ths round; yet this last tree was considerably less than the first when removed, and not planted in a better soil, and yet is 1 foot 1 inch 3-8ths larger than the original tree. The first contained 4 feet 1 quarter 336 inches, and gained 2 feet 3 quarters 220 inches in 16 years: the last contains 8 feet 3 quarters 68 inches; and, supposing them equal in 1743, gained 7 feet 384 inches; i. e. above 2 the increase of the first tree. But notwithstanding the transplanted oak was thus much larger than the original oaks in the grove, yet as the transplanted tree does not run half the height of the trees in the grove before it heads, they differ but little in their quantity of timber.
The great Lord Bacon says, "the improvement of the ground is the most natural way of obtaining riches." What great fortunes might be raised, by those that have property, in the vast heaths and downs, or fields of poor land, in this kingdom, by planting parts of them? which would also add great beauty to the country, and render the dwelling much more comfortable to the neighbourhood, by the shade in summer, and warmth in winter. Some parts of these great wastes would produce good oak; and where the soil is moist, poplar, alder, and other aquatics, would be very profitable to the planter. The chalky soil seems the least promising; yet beeches sometimes thrive well upon it. The fir kind, especially the Scotch fir, will grow surprizingly on poor sandy land; but woods of fir should be guarded with an out-line of birch and beech, to break the force of strong winds. Birch, being the quickest grower, will best protect the young fir; but as birch, after a few years, is easily blown down, so beech will be wanted to defend the firs as they become large for I have seen broad glades made by the wind through great woods of fir in Switzerland which, perhaps, might have been prevented, at least in part, by an outline of beech.
I know some think, that poor land cannot produce large trees; yet the oak at Northall in Hertfordshire, whose beautiful head spreads a circle of above 40 yards diameter, stands on a dry and deep sand; and the fine chestnuts and beeches by Mr. Naylor's grand castle of Herst Monceux in Sussex, grow in a light sandy soil and I have found, by experience, the Weymouth, Scotch, spruce, and silver firs, which I planted in a poor sandy soil, are larger and finer trees, than others set at the same time in much better land. Perhaps it may require a rich clay to produce such trees as the noble grove of oak in the Earl of TT
Powis's park by Ludlow, or Lord Ducie's vast chestnut at Tortworth, in Gloucestershire, which I measured 46 feet in circumference at near 6 feet from the ground.
III. Of some Antiquities found in Cornwall. By the Rev. William Borlase, M. A., F. R. S. p. 13.
In the year 1756 a farmer at Bossens, in the parish of St. Erth, driving his oxen from the field, perceived the foot of one of them to sink a little deeper than ordinary into the earth at A, fig. 1, pl. 13. Curiosity, and the hopes of treasure, led him soon after to search the place; where was soon discovered a perpendicular pit, circular of 24 feet diameter. Digging to the depth of 18 feet, there was found a Roman patera fig. 1 and 2: about 6 feet deeper, the jug, fig. 3: near by, among the rubbish, the stone, fig. 4; a small millstone, about 18 inches diameter: then another patera, with two handles, in other particulars of the shape and size, as fig. 2, but unfortunately mislaid, and not now to be found. Intermixed with these were found fragments of horns, bones of several sizes, half-burnt sticks, and many pieces of leather, seemingly shreds of wornout shoes. Having sunk to the depth of 36 feet, they found the bottom of the pit concave, like that of a dish or bowl. There was a sensible moisture, and mostly wet clay, in all parts of the pit. On each side there were holes at due distances, capable of admitting a human foot, by which persons might descend and ascend. There is no doubt but this work must have been intended for a well but a pit so deep, and of such narrow dimensions, must have been sunk through a stony ground with much difficulty, and with tools very different from those now in use.
Going to the spot on the 22d of May, Mr. B. found, on the higher part of the tenement, in a field called the Rounds, the remains of a fort: the length of it, bearing nearly north and south, was 152 feet; the breadth, from east to west, about 136 feet. The foss on the outside was still discoverable; the walls dismantled, but sufficient remains to show, that the work was rectilinear, with the angles rounded off; a manner of fortifying which the Romans were gene rally fond of, as may be seen by their stations per lineam valli (Horsley Britannia Romana, p. 113, and many other places.) At the north corner, B, there was an additional building, projecting outwards beyond the rampart, about 30 feet long, not quite so wide: at the south angle at D there are the signs of a building of like kind: these were the procestria of the fort. The shape and size of the work, as it stands at present, may be seen in the drawings annexed, fig. 8. On examining the rubbish near the pit, he found the cut stone, fig. 5, part of a large stone vase, and part of an earthen sepulchral urn: he found also some fragments of leather: al which, with what was found before, are briefly
Fig. 1 and 2 are two views of the patera: it was made of tin, the 20th of an inch thick, 44 inches wide at the brim, but narrowing downwards, was at the bottom, which was flat, 2 in diameter. The bottom of the inside is represented, fig. 1. Fig. 2 is the side of the same patera, by the scale annexed. It is very rare to find these seemingly trifling cups and dishes inscribed to a particular deity; but most uncommon to see them distinguished by the names of the donor and his father, as well as the name of the deity to which they were dedicated. This patera, found at Bossens, about 3 miles north-east of St. Michael's Mount, is a singular instance of the latter usage, and has an inscription engraved on its bottom, in a circular line, as in fig. 1. Which Mr, B. reads thus: Livius Modestus Driuli (or Douiuli) f. (for filius) Deo Marti. The first 2 words are very plain (though, like the whole, a mixture of Greek and Roman characters,) and not rare in Roman history.
Fig. 3 is a jug or jar of tin also, containing 4 quarts 1 pint and of a quartern, wine measure: its weight 7 lb. 9 oz. It is the præfericulum of antiquarians, a vessel used to bring the holy water, or other sacred liquor, to the altar. Fig. 4 and 5 are of stone. The first and largest weighs 14 lb. 1 oz. avoirdupois, and 11 dwts. amounting to about 18 lb. Roman and 337 grains. The second and smaller stone weighs 4 lb. 1 oz. and 7 dwts. or 54 lb. Roman and 95 grains. By the holes these stones have near the top, they were probably designed as weights, by which provisions were bought for, and afterwards shared among the soldiers of the fort. Fig. 6 is part of a vase or bowl, sometimes made of brass, or richer metal, but here of stone. This vase was of curious grey granite, formed by turning, well polished within, somewhat discoloured without, as if it had suffered by fire.
The small millstone, by the smoothness of one side, shows that it had been much used; and was such, without any material difference, as is now used in the islands of Scilly (and elsewhere) for handmills to grind corn in times of siege and confinement, and must be absolutely necessary in all forts. The bones and horns may be supposed to have belonged to animals, either sacrificed, or killed for the sustenance of the garrison: the ashes and half-burnt sticks, are the remains of sacred or culinary fires. The fragments of leather are for the most part patched, and coarsely sewn together; but one piece, found more entire, may contribute perhaps to show the shape of the Roman calceus of those times; and may be seen fig. 7, by the same scale with the rest. Some bits of leather were also pierced with circular holes; but whether parts of the calceus, cothurnus, or any border for the habit, armour, or vehicle of the officers, enough does not remain to decide.
I shall make no other reflection at present on these antiquities, says Mr. B.,. than that the inscription is the first discovered in this county of such high
antiquity; and will satisfy the learned, that the Romans had penetrated into the westernmost parts of Cornwall before the empire became christian: that the sacrifical vessels, the pateræ, and præfericulum, are of tin, the natural product of Cornwall: the vase, the weights, the millstone, are also of Cornish granite: and by the walls, the religious utensils, the weights, the quantity of shoes, bones, horns, vases, urn, and ashes, this fort appears to have been that of a fixed garrison, not a temporary occasional fortification: that by the shape of this fort, and the antiquities discovered in it, it was a Roman fort.
IV. A New Improved Silk-Reel. By the Rev. Samuel Pullein, M. A.
The improvements made in the reeling, and other operations relating to silk as well as cotton, have been so numerous and much more important since the date of this paper, that it was deemed quite unnecessary to reprint it in these Abridgments.
V. Experiments on several Pieces of Marble Stained by Mr. Robert Chambers. In a Letter from Mr. E. M. Da Costa, F. R. S. p. 30.
But before relating the experiments, it may not be improper to give some little historical account of the art itself. Kircher, in his Mundus Subterraneus, lib. viii, sect. 1, c. 9, p. 45 and 46, is the first author that mentions it. There was, says he, an artist at Rome, who painted several pieces of marble, in an elegant manner for Pope Urban VIII. He would not discover his art; therefore Kircher strove by many experiments to discover it: and he made colours, viz. tinctures of metals and minerals, which coloured the marble as finely as any the artist had done, and quite penetrated the stone; insomuch that a slab cut horizontally made as many pictures as pieces or sections. Kircher gives at large the process he used for making the colours; and observes they should always be of a mineral origin. The said author (Ibid.) also gives another method to colour marble, by vitriol, bitumen, &c. forming a design of what you like upon paper, and laying the design between 2 pieces of polished marble; then closing all the interstices with wax, you bury them for a month or 2 in a damp place. On taking them up, you will find that the design you painted on the paper has penetrated the marbles, and formed exactly the same design on them. A modern author, Wallerius, in his Mineralogy, vol. ii. gen. 58. p. 128. also recommends this method.
In the Phil. Trans. N° 7, Kircher's first method is copied. The editor however says, that method has not since been tried. He adds, that one Mr. Bird had for many years (he writes in 1666) found out a way to sink colours a considerable depth into polished marble; pieces of which were shown to King Charles 2d, soon after his restoration; and, being broken in his presence, it
was found that the colours had penetrated deep into the marbles; and that many works of his coloured marbles were seen at Oxford and London. But Mr. Bird's way of doing it is not mentioned.
In the Philos. Trans. N° 268, is a paper, intitled, "The Way of Colouring Marble." The anonymous author gives an account of the colours, &c. he used. It is observable that they are only vegetable colours. His red, he says, he extracted again from the marble, without hurting the polish, within 26 hours, with oil of tartar per deliquium; and his brown was quite discharged by aquafortis within one quarter of an hour, and the polish of the marble quite destroyed.
Mr. da Costa now proceeds to give an account of the experiments he made. He could not well suggest any more, as the method of colouring the marble, the materials of the colours, &c. are kept secret by the artist, Mr. Chambers.
A piece of marble with the several colours used, on it, like a painter's pallet, being greatly saturated with aquafortis, at different times, for 24 hours, though the polish of the marble was quite effaced, yet there was not the least discharge of any of the colours, nor were they any-wise dulled, &c.-N° 6. A deep crimson-red colour, being left 20 hours in a strong lye of common soft green soap, suffered no change; and boiled in the same lye half an hour, also suffered no change. The marble finely powdered, and aquafortis effused over it, the marble particles were nigh destroyed; but several red particles (no doubt the colour) remained. The marble, by common calcination, i. e. in a common coal fire, for half an hour, is entirely discharged of its colour. We made the experiments on four other reds, and the result was much the same as abovesaid; so that this is a standard for his reds.
N° 5. A deep sea-green, being left 20 hours in a strong lye of common soft green soap, suffered no change; but boiled in the same lye it quite discharged its green colour: however, it yet remained slightly tinctured yellowish. By common calcination the colour was quite discharged. Some other greens were tried, and answered much the same.-N° 10, 15, and 16, brownish or terrestrial yellowish colours, near to a clay colour, boiled in a strong lye of common soft green soap, they suffered no change. By common calcination the colours were discharged, but retained a greyish cast. These colours, covered for 48 hours with a layer of the said common soap, suffered no sensible change.—No 19, A bright yellow, boiled in a strong lye of common green soft soap, suffered no change; and covered with a layer of the same soap for 48 hours, the colour is dulled. By common calcination the colours are discharged, but retain a greyish cast. Several other different shades of yellow answered much the same. Mr. Chambers has not as yet stained any marble of a blue colour.
By the above experiments we may conclude, that these colours are good, penetrate the marble freely without injuring it, remain uninjured by menstrua,