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I have also often seen moles of very close mown grass, and bare spots in pasture land, plunge,, when alarmed, among the roots; following their path (which was discernible by the heaving of the surface); I have forced them out occasionally, to try the depth of the covering, which was only a few shreds of roots.

There are two circumstances that may oblige moles sometimes to penetrate deeply:-disturbed soils in summer, such as in gardens; and ploughed light lands, where the moles delve in pursuit of worms; and, in their course, they must unroot and destroy some plants; but a vigilant gardener and husbandman will prevent much damage.

The other cause of their digging deep is frost, which they avoid, or it would kill them. I have found them in winter, in peat soil, two and three feet below the surface; and in the hard frost of 1794-5 (cutting deep trenches to separate grounds), I found moles several mornings, that had worked through and fallen into the trenches, frozen to death.

Their summer emersion is proved by the birds of prey: they destroy great numbers of moles. This year there were taken out of one kite's nest twenty-two moles, and out of another fifteen, some of which were putrid; besides many frogs and unfledged birds.

The rapacity of the kites shews that they are destructive enemies to the moles, which, if moles are serviceable to man, should be known, that he may stay his arm.

Moles are frequently found dead upon the grass in summer, with marks of having been bitten, as if to suck their blood, but with ne part of their bodies consumed. This, I suppose, is done by weasels; and the following (not very common) occurrence, which happened in the summer of 1789, tends to prove it:

A kite was observed rising from the ground with some prey, and instead of flying to an adjoining wood, he soared almost perpendicularly. After remaining a short time stationary, he came gradually down, with his wings extended and motionless, and dropt very near the place from which he had risen.

Several persons who were near, and saw the flight and descent, ran immediately to the spot, and a weasel darted from the kite, which they found dead; and they discovered, on examination, that the kite had been bit in the throat, and bled to death. Near it they found a dead mole, yet warm, which was bitten in the neck; and they concluded that the weasel had caused the death of both.' F. 177.

The last communication in this division is a very valuable one, as it shows that a strong rich manure may be produced from lime and peat-earth. We would, however, advise the experiment to be repeated.

In the class of chemistry, we find an account, from Mr. Bentham, of a method of keeping water sweet during long voyages. This gentleman's idea is, in many respects, a very correct one, that water is tainted by the wood. He proposes, therefore, to keep the water in tanks, made of tinned copper sheets, or rather in wooden vessels lined with these sheets, soldered so

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nicely as to prevent the access of the water to the wood. This method will, undoubtedly, be an effectual one; the tanks can be more conveniently stowed, and there is not so much danger of the water starting, as it sometimes does by the casks rolling. But as charring the staves on the inside is a precaution equally successful, it remains to be determined, whether the conve niences stated are equal to the difference of expense. The only other communication in this class respects the inspissated milk of lettuces. It seems, in one solitary instance, to have produced all the effects of opium, given in about a double dose, It produces, however, its disagreeable effects also. Mr. Cartwright supposes, that, if the juice of lettuces can be rendered valuable in this way, the vegetable may be afterwards useful for feeding hogs.:

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Mr. Sheldrake's paper in the class of polite arts, though subservient to these, is chiefly chemical, and has, in substance, appeared in the former numbers. The principle of our author's discovery is, that in drying oils there is a mucilaginous substance, which separates spontaneously; and that they act as such, by the mucilage rising to the surface, when employed in painting, and there hardening. Metallic calces, and every substance which increases the drying power, increase the separation of the mucilage alone, and injure the colours. Our author substitutes amber and copal with success; and the methods of dissolving these substances have been copied in our journal. Mr. Sheldrake's observations on this subject, and his arguments to show that this was really the varnish employed by the painters of the Venetian school, if not perfectly satisfactory, render his opinion highly probable.

Under the class of manufactures we find a very good common paper, almost as good as is employed in printing some of the German classics, prepared from a vegetable substance, which in Bengal is used for making coarse bags, ropes, &c. It is called the paut plant. Of this there are two species, the corchorus olitorius and capsularis Linn. It certainly may be advantageously resorted to in the coarser papers; but the price of rags has now fallen, in consequence of the peace-though we mean not most remotely to insinuate that our continental neighbours are more ragged than ourselves.

The root of the chicoree plant is employed in Germany as a substitute for coffee. It is the cichoreum intybus L. and is cultivated for that purpose. The cultivation and manufacture are described at length in the paper before us, but are not sufficiently interesting to detain us.

Under the head of mechanics is a very simple machine for raising water by Mr. Serjeant: it is described and illustrated by a plate. This is followed by an account of three whales struck by the 'gun-harpoon; but we see no evidence to prove

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that they might not have been killed by the common harpoon.Mrs. Besant's improvement of the undershot wheel, chiefly adapted for back water, deserves the attention of mechanics, as possessing some advantages over the common wheel, and having greater powers of action. Mr. Phillips received the gold, medal for his improved method of driving copper bolts into ships, without bending them or splitting the heads: his method, as well as his punch and tubes, are particularly described.-A' description and plate is also inserted of Mr. Arkwright's machine for raising ore from mines.

Mr. Evans has discovered a quarry of the burr-stone in Montgomeryshire, equal to the French burrs. It was found on the western confines of Montgomeryshire, bordering on Shropshire, about a mile and a half distant from the Severn, whence the conveyance is easy to every part of the kingdom.

Mr. Terry received the silver medal for his mill, calculated for grinding hard substances, as bones, ashes, coffee, &c. A description and plate are annexed.

The advantages of Mr. Bullock's drawback-lock for housedoors-of which there are also a description and engravingconsist in the great facility with which the bolt shoots. The door, in falling fast, therefore, always catches with little noise; and it is very easily opened, viz. with one-twenty-fourth part the force necessary to open common locks of this kind.

Mr. Gent's crane, or machine for raising heavy weights, and ore from mines, has a double advantage; viz. of making a perpendicular draft, and discharging the load without any intermediate space; and, 2dly, of raising it to a sufficient height, so as to place the article in a cart or carriage.

Sir George Onesiphorus Paul's communication, on the ventilation of hospitals, is truly valuable, as equally simple and ingenious. It consists in communicating the ventilating funnels with the fire, and thus increasing their power by the rarefaction of the heat. Sir George's letter is however somewhat verbose. The real substance might be comprised in three pages. M. de Lafon's account of the merits of his new escapement for watches we cannot give in shorter words than his own.

Having considered the perfection of chronometers to consist more in giving an equal impulse to the balance than to any other general cause, I present, in hopes of the approbation of the society, the model of a new escapement, which has not only the property of correcting the errors of the main-spring, train of wheels, &c. and giving an equal power to the balance, but likewise the wheels are locked, without spring-work, perfectly safe from getting out of order, and are unlocked with less power than in any escapement I know, as the wheels do not bear against the locking with more than a tenth part of the whole pressure from the main-spring; a circumstance I believe to be perfectly new.

Although the giving an equal impulse to the balance has been already most ingeniously done by Mr. Mudge, and by Mr. Haley (from whose great merit I would not wish to detract), yet the extreme difficulty and expense attending the first, and the very compound locking of the second, render them far from completing the desired perfection.' P. 331.

In the department of colonies and trade, we find a valuable communication respecting the application of myrobalans, as a substitute for galls. The astringent power of these nuts resides almost exclusively in the pulp; and they furnish all the different shades of buffs, with different mordants. There were many kinds of myrobalans formerly employed in the materia medica. That most useful, as a dying substance, is the phyllanthus emblica of Linnæus.

Stick-lack has also furnished a very valuable lake, little inferior to cochineal. A very interesting account of the insect, and the different manner of separating the beautifully red fluid, is given in a letter from Dr. Bancroft. The following extract deserves particular notice.

I had found, more than twelve years ago, that the true or natural colour of cochineal when given to wool by dying, with the common solution, or nitro-muriate of tin, which the dyers invariably employ for dying scarlet, was not a scarlet, but a bright rose colour, as No I. of the samples which accompany this paper; and that in the usual process it only became a scarlet from the chemical action of the acid of a considerable portion of tartar, which the dyers invariably use; though without knowing the particular effect resulting from it.

No II. is a sample of a very beautiful scarlet, dyed by the successor of the late Mr. Nash, in Gloucestershire, and like all true scarlets is a compound colour, of about three portions of the rose of No I. and one portion of pure yellow; though in this instance the effect or colour results not from the addition of a foreign yellow, but from such a conversion of the cochineal rose colour towards the yellow as is equivalent to about one fourth of the whole. Reflecting on this fact, and considering the great difference in price between the colouring-matter of cochineal and that of the purest known yellows, I concluded that a great saving of expense might be obtained by employing the former without tartar, so as only to produce that portion, which is necessary, of the rose colour, and superadding a suitable portion of yellow from some of the cheaper yellow dying-drugs; among which the quercitron-bark naturally occurred to me as producing, with the solutions of tin, one of the purest and brightest yellow colours; of which a sample may be seen at No III. Upon this principle the sample N° IV. has been dyed; by first giving the cloth a yellow ground, with a suitable quantity of the usual solution, or nitro-muriate of tin, and of the quercitron-bark, and then superadding the cochineal rose colour, by dying it in the usual way with cochineal, and a like solution of tin as for a scarlet;

taking care only to omit the tartar, which would otherwise have car. ried the colour so much farther towards the yellow hue as to produce an aurora. P. 361.

The colour of lake is about one quarter of that of cochineal'; four pounds of the former being required to perform the office of one pound of the latter.

An account of the rewards bestowed by the society, and the list of the members,-which is much more extensive than ap peared in the former publications,-conclude the volume.

ART. V.-General View of the Agriculture of the West Riding of Yorkshire. Surveyed by Messrs. Rennie, Brown, and Shirreff, 1793. With Observations on the Means of its Improvement, and additional Information since received. Drawn up for the Consi deration of the Board of Agriculture and internal Improvement. By Robert Brown. 8vo. 6s. sewed. Robinsons.

OUR author will not find that the majority of farmers agree in every part of his eulogium on the Board of Agriculture; nor will critics, in general, admire the wisdom of entrusting surveys to strangers. To strangers, indeed, who are free from local prejudices, every custom will appear in a more new and striking light; yet prejudices in favour of their own practice may, on the other hand, improperly bias their judgement. A great source of error however will be, that a stranger is on these occasions viewed with a little jealousy and mistrust. Many will be cautious of giving information; and some, we fear, may mislead. A stranger cannot always appreciate his authorities; nor can he easily decide when discordant opinions-as, on agricultural subjects, such will often happen-are offered to him, Perhaps what was done in the survey of Lincolnshire-though we must still blame the rejection of Mr. Stone's labours without having assigned a reason-may be most advantageous; viz. after receiving the account of a resident surveyor, a direction that the whole be re-examined by a man of real knowledge and competent judgement. Had Mr. Rennie and his companions enjoyed an anterior survey, they would have executed their task more successfully than they have done-the path before them being in this respect new and unexplored.

The western district is on the west and south of the other parts of the county; bounded on the west chiefly by Lancashire; and on the south by Nottingham and Derby shires. It is in itself a considerable county, containing more than a million and a half of statute acres. The county, except on the east, in the neighbourhood of the Ouse, is high, and catches the clouds from the Atlantic in common with the mountains of West

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