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is dever bod to a German work parushed n the early pin fast tent. Lep The Matar ar contraste is Lierse paused a the trite 2-a work, A TWAL Noose Tag; and also in the afferent Engg pria, as The British, Hall, and others, under the taze å dr Jans, and all more, that suca Ar Jakes were upwards of 20 years since commodly exposed to sue, together with Cork Jackets at the trunk-makers in Lisie. Now I am upon the subject of Cork Jackets, permit me to add, that a much smal er quantity of cork than is commonly supposed, sufficient to support the human body in water; for two pieces, about three maniers of an inch thick, and eight or nine in bes square, enclosed in calico, flannel, canvas, olled silk, &c. and one of each fixed beneath the arm-pits by means of two straps or tapes passing over the shoulders, and two others to tie them round the body, are quite sullent to keep the head and shoulders out of the water, either in standing erect therein, or in swimming, &c. and, I believe, will be found the best mode of applying cork to so valuable a purpose. It might be well to make hollows or depressions in the upper edges of the corks, rounded off so as to fit the arms better; and, if the pieces were either chosen bent, so as to be close to the ribs, or bent by heating them, it would be better.

I am, Gentlemen,

your most obedient servant,

T. G.

Graham's

Graham's Dead-Beat improved.

By Mr. R. KING, of Scarborough.

With an Engraving.

Communicated in a Letter to the Editors.

To draw this escapement, having drawn the wheel

with its thirty teeth, and marked off the half tooth required for the progressive motion of the wheel, then from the centre of the wheel through the points e and g draw the lines D E, Fig. 12, (Pl. XVI.) and D F; then from the points e and g in these lines draw the tangent lines g Cand e C intersecting each other in the point C, where the centre of the verge must be fixed; then through the point of the tooth h draw C K, being the line of impulse; then at the angle of 45o draw the line L B, which gives the inclined plane of the pallet B, which being continued to the line D E, forms the face of the pallet; then through the point of the pallet draw the line C M, being the line of its escape; then draw the line CN through the point of the tooth i, the line of its escape, and with same angle as K CM, draw the line of impulse to the pallet A, and at 45° draw g P for the face of that pallet; then draw the body of the pallets completing the whole.

The improvements I have added to this Escapement, are, that the face of the pallets act at an angle of fortyfive degrees, instead of sixty, which was the angle used by Graham; the angle of 45° acting with more freedom without checking the vibration by the impulse; and I also place the centre of the pallets in the intersection of the tangent lines, by which means the friction of swinging into the teeth is abated. It yet remains

with

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with difference of power in the action of the pallets, the tooth that swings the pallet on the right-hand side in the drawing, gaining power in the impulse by getting to a greater distance from the centre of the verge, while the left-hand pallet loses power by its approach to the centre; yet, with these inconveniences, it is much better than any Escapement, with locking and loosing detents.

I am, Gentlemen, yours, &c.

R. KING.

Scarborough, May 30th, 1808.

Account of the Wheat Moth, or Virginia Fly; as it appeared in France in the year 1755; and which damaged the Grain in the Township of Lower Dublin in the Harvest of 1802, 1803, and 1804.

From the LETTERS and PAPERS of the BATH and WEST of ENGLAND SOCIETY.

THE

HE inhabitants of a considerable part of the province of Angoumois, in France, had for a period of thirty years sustained an immense loss by the ravages of this insect. It appeared at first only in a few hamlets, but soon made so rapid a progress as to spread to the lands of upwards of two hundred parishes. In the year 1755, Messrs. Duhamel and Tillet were deputed by the Academy of Seiences at Paris, of which they were members, to enquire into the nature of this insect, and the means of preventing and curing the dreadful calamity occasioned thereby. The description given of it by these gentlemen is so minute and particular, as to leave no room for doubt of its being the same we have in America. It resembles the moth which preys upon woollen

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