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A is the ash pit; C the grate; D the door for the fuel; G the cavity where the metal is laid. The flame passes over it and up the chimney, F. H is the door for putting in the metal; in the bottom of this door is a square hole for putting in the rake and other tools used by the puddler in working the metal, who can at the same time see the process through this aperture.

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MR. PERKINS' ACCOUNT OF HIS STEAM-GUN.

"Observing, while experimenting with the generator, that substances, whether metallic or otherwise, when they rose from the bottom of the generator through the tube of the stop-cock, were projected with great velocity j the thought naturally struck me, that with a properly constructed gun, projectiles might be thrown with great power and economy. It also appeared to me, that it would at once settle the important question respecting velocity, as well as power of high elastic steam. No time was therefore lost in constructing a gun, and on the first experiment my most sanguine hopes were realized, as musketbails, at the rate of 240 per minute, were projected with a velocity equal to gunpowder. I dare not speculate on the consequences of this discovery, as I feel satisfied, that the power, economy, and simplicity of this agent is such, that one projectile may be found sufficient to force any breach, or sink the largest ship, though it gives me great pleasure to hear the opinion so often repeated, that this power will be to gunpowder what that has been to the airow.

"I have found that forty atmospheres' pressure is equal to gunpowder; viz. an ounce ball discharged against an iron target from a six foot barrel about one-thirtysecond part smaller than the ball, was flattened to 2j inches in diameter; and at 45 atmospheres, its blow against the target liquified the lead. An ounce ball discharged from a musket with powder, with the common field charge, at the same distance, did Dot show more effect. It is said, with great plausibility, that there must be some fallacy in this experiment; for as it takes from 500 to 1000 atmospheres' pressure to propel a ball with proper effect with powder, it is asked, how can it take but 40 or 50 atmospheres of steam to do the same? Having the fact before me, I think I can find the reason, which I have no doubt is the same as'that, why fulminating powder, although infinitely . stronger than gunpowder, will not (though it bursts the gun) throw the ball one-twentieth part so far, the power being too instantaneous for projectiles; gunpowder being less so, gives greater effect, although the mechanical pressure is much less. Steam power, acting with constant pressure on the ball until it leaves the gun, in consequence of the nondiminishing g-eneration of it, is, I believe, the cause of the increased effect." March, for those growiDg in the open air. But (says Mr. Braddick) otit of 40 or 50 vines which I operated on in the above months, few grew, and those which did grow were weakly, and were as long before they bore fruit as if they had been seedlings planted in the place of old vines. He observed that all the plants bled profusely, and he tried to stop this by various means, but all without effect. One experiment, he says, I will mention, as it will serve to show the great power of the rising sap in the vine while its buds are breaking. On the 20th of March, in the middle of a warm day, I selected a strong seedling vine, five years old, which grew in a wellprepared soil, on a south-west wall. I took off its head horizontally with a clean out, and immediately observed the sap rising rapidly through all the pores of the wood, from the centre to the bark. I wiped away the exuded moisture, and covered the wound with a piece of Madder, which I securely fastened with cement, and a strong binding of waxed twine. The bladder, although at first drawn very close to the top of the shoot, soon began to stretch, and to rise like a ball over the Wound. Thus distended, and filled with the sap of the vine, it felt as hard as a cricket ball, and seemed to all appearance as if it would burst. I caused cold water from a well to be thrown on the roots of the plant, but neither this, nor any other plan that I could devise;' prevented the sap from flowing; which it continued to do with so much force as to burst the bladder in about forty-eight hours after the operation was performed, the weather continuing the whole time warm and genial. After some further experiments, it occurred to Mr. Braddick, "that the proper time for cutting off the heads, and grafting of vines.without incurring the dangerof their suffering through bleeding, was when they had reached that period of thcir annual growth at which the sap ceases to flow ihjnjy and rapidly. I accordingly cut the branches of several in that

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QUERIES.

To the Editor of the Chemist. Sik,—I shall be obliged if, through the medium of your valuable little work, The Chemist, you could obtain me an answer to the following question:—

What are the component parts of a precipitate that is obtained by mixing solutions of morphine in prussic, and quinine in sulphuric acid, together?

As it is a subject of some importance to me, I shall "be particularly obliged by your inserting the above.

Yours, very respectfully,

Morphine Iodine.

How to prepare a durable ink, which will write faintly, but become very black on drying?

H. S.

Mr. Chemist, — Admiring the obliging and liberal manner in which you have answered the inquiries of some of my acquaintance, I take the liberty of troubling you (hoping you will excuse the curiosity of a young beginner,) to

State, and grafted them with the cuttings of the preceding year. All these grew; the operation being that of whip-grafting, and no other covering was used than a binding of bass, surrounded with grafting clay. From these, and various Other experiments which I have since made, I feel confident in stating, that healthy vines may bo successfully grafted with young wood of the preceding year's growth, from the time that the shoots of the stocks in which the grafts are to be put have made four or five eyes, until Midsummer, with every prospect of the grafts growing, and without the least danger of the stocks suffering by bleeding. They may likewise be grafted with shoots of the same summer's growth, worked into the rind of the young wood, from the time that the young bunches of grapes become visible on the stocks, till July, out of doors, or till a month later under glass. The operation must not be performed later than the period here specified, because time is necessary for the young shoots of the grafts to become hard, and ripen before winter—(From the Transactions of the Horticultural Society.)

PARACELSUS.

Mr. Editor,In the early history of chemistry no name is more famous than that of Paracelsus. Dr. Thompson says of him " that he was an impostor, and boasted of secrets which he did not possess; that he stole many opinions and facts from others; that his arrogance was insupportable, and his bombast ridiculous; and his whole life a continued tissue of blunders and vice." If it were not that no memorials are so false as those which are inscrihed on tombs, I should be disposed to believe Dr. Thompson's estimate of the character of Paracelsus somewhat erroneous. The following simple account of the inscription over the grave of Paracelsus is from a German author. "According to the monumental record on the church walls of Salzburg, Aurelius Theo

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TNFfiliMlKfe GUNPOWDER

-^By. Electricity:

"ttfilie ^Mloriff the Chemist. Si*,—In pip 68, Art.X. of the Analysis of the Annals of Philosophy, is an account of some experiments' .&f IVtV. Woodward on the firiiifrof loose gunpowder, which I bOTTetfi.W?j&' notice is far from being original, the same experiments naving been performed by WfK jjewthwaite, of Princes-street, RoWerMthej an account of which he^'Writjllsued, in the Journals of the' ftovaj institution about two yeifr^raclc. The firing of loose gunpowder was published about 20 years ago, in a book entitled ' Imisonls/Elements,' from which the following is a copy :—

If tho gunpowder be placed loosejy upon any stand, and the interruption of the wire circuit be made.; ia it, on making the discharge of the jar, llie spark which take* place at the interruption will scatter the gunpowder without iiriogl>ifa"!But tbe loose gunpowder may be fired if the shock be transmitted through less perfect conductors; in wbich case the discharge being less sudden, or rather proceeding in a stream, the powder will be fired, i The best method of performing this experiment is that of Cavallo, which is as follows :—

F represents, .the gunpowder placed upon the same table upon wbicfi'tneW. Ai hftfttfateif; B is aglakjftub'e, aboiii: one foot long arid tftfuwtfeT'of ail inch iidiameter,s«ffl1df'watei', a$d' having two corks Witt ex'trernftieS. Into these two corks two wires' are thrust, the

inner extremities of which just touch the water, viz. the short wire, F, and the long wire, C, which makes the communication between the water of the tube and the knob of the jar. On making the discharge, whjch must pass through the small quantity of water in B, and down to the table,. F, in the form of a dense stream, which generally fires the gunpowder.

Now you perceive, Mr. Editor, that neither of these, gentlemen have yet made any. discovery in firing gunpowder, which plainly appears to have been done near 20 years ago.

Yours, truly,

A Young Philosopher.

. i, UlRM* I ,1'UJ -if it-

We beg leave to observe to our Correspondent, that Mr. Woodward's experiment is not curious from tiring gunpowder by means of the electrical spark, but as showing the effect of different conductors. With good conductors the gunpowder was blown away, which is the curious part of the experiment, for the inflaming power of electricity is known to be sufficient to molt iron; but in this ins'.ance, the rapidity or mechanical force with which the stream of electricity was transmitted by good conductors, was sufficient to prevent its chemical power from operating, and, the gunpowder was not inflamed, but blown away. The ex- < tract of our Correspondent, at the same time, shows satisfactorily, that even this part of Mr. Woodward's experiment was not new. —ed.

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