and with this, and the sliding piece D, it forms the common gauge used for describing parallel lines from the edge of any piece of wood-work; the addition made by

Mr. Palmer consists of two brass arms E and F, of equal length, which are centered in the two sliding-boards, or cheeks, at a a: the other ends are jointed together by the screw G, which is formed into a sharp point beneath to mark the work with. In using this guage, its two cheeks BD must be set to the width of the piece of wood intended to be scribed and applied, as shewn in Fig. 2; it must be evident, that the point of the screw G, will always keep in the centre between the two cheeks BD, because the two arms E F, are of equal length, and

a line joining their centres a a is perpendicular to the cheeks; it may also, as before stated, be used in the manner of the common carpenter's gauge by means of the sliding cheek D, and the marking points projecting below the bar at b. This tool will prove much more expeditious in use than the usual method practised by carpenters for finding the centre of any piece of board, &c. viz. by setting the common gauge, as near as can be estimated, to the centre of the piece, and making a mark, and then turning it to the opposite side of the piece, and making another mark, between which, if the distance is made very small, will be found the centre, 'near enough, for common purposes.

If the piece of work to be gauged is not parallel in its width, then the screw C must be loosened, and the two cheeks kept pressed together with sufficient force to keep them in contact with the two sides of the work, when the point G will traverse along the centre as correctly as if it was parallel; because, in all situations it preserves an equal distance between the two cheeks. The two cheeks have grooves in them to admit the brass arms E and F, when the cheeks are brought into contact.

On a Remedy against the Ravages of the Fly on Turnips, and Swedish Turnips. By THOMAS GREG, Esq. From the COMMUNICATIONS of the BOARD of AGRICULTURE.

As the Board does me the honour to request I should make known to them the experiments I have made with lime, under the directions of the earl of Thanet, particularly how and when it should be slacked, and how and when applied,—I shall, in conformity to their request, give in detail my own experiments thereon.

I had the honour of paying lord Thanet a visit early in the spring of 1811, at which time he had began to sow Swedish turnips.

On that part of the field which his lordship mentions as having failed, the application of lime was omitted, at my particular request, the better to demonstrate the infallibility of the experiment.

Upon my return to Coles, I ordered lime to be laid upon, the headlands, proportioning the quantity to the length of the lands.

The weather was fine, and the lime did not fall by the atmosphere, but was slacked as used, and sown by hand over a 40 acre piece of land.

I ordered every day's sowing to be watched, and the lime to be applied as soon as the turnips came up, in the same daily rotation as they were sown, which was 5 acres per day.

But as lord Thanet properly observes, "to have any experiment made, you must see it done." This remark was verified, by the neglect of the bailiff in my absence, who delayed spreading the lime on the first and second day's sowing, until the third day's sowing was ready; which delay and mistaken economy in labour, exposed the first day's sowing to the ravages of the fly.

But this circumstance I cannot lament, as it furnished additional proof of the efficacy of the lime, and procured the correct execution of my orders upon the remainder of the field, which 35 acres were covered with healthy plants.

In the year 1812, I repeated the same process, with the same success; and I have not the least doubt, but lime is an infallible protection to the infant turnip, if rain does not immediately succeeding the sowing. If it does, on the return of fair weather, I should recommend a repetition.

The

The casting of lime by hand produced considerable inconvenience to the men, in consequence of which the work was not well performed: however, under that disadvantage, the turnips sown upon 40 acres of land, in 1811, were so abundant, as to support 500 down sheep, about 6 cows, and 30 hogs, until May, 1812; and the crop of 1812, consisting of the same number of acres, will, I have no doubt, support an equal stock to the same period.

Impressed with the importance of the application of lime, and finding it necessary to deposit it with great accuracy, I turned my mind to machinery to effect that purpose.

Without troubling the Board with a detail of experiments, it is with great satisfaction I am enabled to inform them, that by adding an horizontal motion into the top hoppers of a common drill, and substituting sinall shovels instead of cups into the lower, I produced a regular discharge of the line.

For dusting turnips in rows, the common seed tin pipe may be used. For broad-cast, they are taken away, and a board, about 18 inches wide, substituted in their place. This board must hang upon an inclined plane, and should be tinned, to facilitate the fall of the lime.

When the atmosphere is damp, the lime will hang upon the board, unless a concussive motion is given to the board, by a crank.

The lime should not be slacked or sifted until the apparatus for sowing it is in the field; for the least damp will change it from a prepared state of powder, and interrupt a regular discharge.

It is not at present in my power to make any further observations to the Board upon this very important branch of agriculture.

The

The pride I feel in having introduced that invaluable plant, the ruta baga, into England, in the year 1785, will be much increased, should my subsequent endeavours be instrumental in protecting and facilitating the cultivation of a plant for which I must naturally feel a kind of parental interest.

Notice upon Alcohols or Spirituous Liquors, and on the Changes which they undergo by their Rectification with alkaline, saline, and earthy Matters, &c.; followed by a simple Process for obtaining the most dephlegmated Spirits of Wine, without altering its constituent Principles. By M. DUBUC.

From the ANNALES DE CHIMIE.

DURING

more than two centuries intelligent men have successively proposed different methods of taking from common brandy a certain quantity of water, of malic acid, and other foreign bodies, which it obstinately retains, in order to reduce it to its most simple elements, to compose a liquor known by the name of alcohol, or highly-rectified spirits of wine.

But it is about one hundred years that Boerhaave, Cartheuser, Sthal, and other chemists, occupied themselves with this object, and that, by means of their processes, this fluid has been obtained almost entirely freed from the heterogeneous matters which alter or debase its properties. Of all the methods indicated by the ancients, that of Lemery appears still to obtain the preference; it is known that it consists in distilling in a vapour-bath brandy, at 22 degrees, in a matras with a very long neck, furnished with a cap, &c.

The alcohol thus distilled, or that extracted by similar' methods, marks in general from 38 to 40 degrees of the

ordinary