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Mechanics' Magazine,

MUSEUM, REGISTER, JOURNAL, AND GAZETTE.

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DESCRIPTION OF A PAPER-DRYING APPARATUS EMPLOYED AT THE IMPERIAL PAPER-MILL OF PETERHOFF, IN RUSSIA, INVENTED BY MR. WILLIAM REED.

(Concluded from our last No. p. 275.)

D is a section of the thin copper rollers, which are only hammered by a good coppersmith. Brass ends,

turned and soldered in the four rollers carrying the endless felt, have edges cast on a little lower to allow the double edge of felt to rest on, as it requires guide wheels-three pair on each side-to keep it stretched. The reels E are round or square, as required (flat reels we have thrown away).

When the dry paper is wound about 500 times, we cut it off from the reel with knives made of handsaws, backed with a piece of sheet-iron to keep them stiff. Four at a time in use will last a year, if good.

It may be as well to notice, that in making the first pair of copper rollers, marked No. 2, the copper must be full a quarter and sixteenth brazed and hammered true; otherwise, in turning, the slide-tool will find its way through it before it is round. The brass-tube gudgeons are let in about two inches into the end; drove

very tight, and well soldered; because, on account of the great distance from the bearing required by the driving riggers and valve for escape of condensed water, they would be apt to get slack. I likewise screwed copper

screws through the tube and brass end, and they are now as firm as the first day. At the delivery from the clarionet-valve there is a small tube with a hole in its side to guide or prevent the water splashing or wetting the paper as it falls into the trough marked No. 10. The steamrollers, felt-drum, reels, &c., are all driven by straps from the machinecylinders marked No. 1.

The cost of a set of such steamrollers is about £250, without the boiler; copper in sheets being 11d. per lb. and cast-brass 16d. to Is. 8d. per lb.

I should have mentioned that the cast-iron forked bearings, No. 9, have on the top a piece of iron with a stout wire pin to keep the roller in its place, and likewise a small funnel for holding suet-it not being so soon melted. If the rollers get dry they

soon cut.

I am, Sir,

Your obedient servant, WILLIAM REED.

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292

BRAITHWAITE AND ERICSSON'S BOILER.

MESSRS. BRAITHWAITE AND ERICSSON'S

BOILER.

SIR, The last attack upon me by your good-tempered and disinterested correspondent, "F," affords the most perfect illustration that I ever met with of that homely proverb, which says, There are none so blind as those that won't see."

In spite of common sense, and the most self-evident truths, "F" persists in endeavouring to deceive the public into the belief, that the boiler in Messrs. Braithwaite and Ericsson's carriage did not give way, notwithstanding all the hot water and steam were forced out of it, through an aperture produced by the excessive heat to which that part of the boiler was subjected! and that the blast which is solely used for augmenting the temperature of the furnace, had no effect whatever in producing the disastrous result, which occasioned "The Novelty" being withdrawn from the late Railway contest! Now, I would inquire, whether it be possible to utter more gross and palpable nonsense? And, I would ask in what light ought we to regard the conduct of "F," who charges me with "substituting fiction for fact," and in "persisting in thrice refuted error most pertinaciously," because I have maintained (and shall ever maintain) the contrary to have been the fact.

If "F" be a man of any experience in the matter on which he writes, he must also know well that wherever blowing apparatuses have been previously employed for exciting the fires of steam-engine boilers, they have uniformly been discarded, on account of their occasioning such a rapid oxidation of the metal. Patch after patch has been "most pertinaciously" laid over the same hole, until the general weak. ness rendered farther patching impossible. This was found to be so troublesome and expensive, and to increase the liability to explosion so considerably, as to lead to the general abandonment of blowing machines. I do not mean to assert that it is impossible so to manage a blast as to render its destructive tendency nearly uniform over the whole surface of the boiler, and by such arrangement obtain advantages for many purposes, which would more than compensate for the early wearing out of the boiler; and I think, Mr. Editor, when you shall have observed the manner in which Messrs. Anderson and James's -boiler is fixed, and that the draught of air is so managed as to cause every tube

to be enveloped by flame, you will be of opinion that a blast might be applied to that boiler without producing any other injurious effect, than the early wearing of it out. Should any part of the tubes become "accidentally" not covered with water, as was the case with "The Novelty," no fears need be entertained on that account for personal safety. But the safe application of a blast to boilers having steam chambers of large capacity, is one of great difficulty; and I have no hesitation in appealing to the good sense of your practical readers, that the manner in which the blast is applied to Messrs. Braithwaite and Ericsson's boiler is as bad as it can well be, which results from the form of the boiler. In boilers of the more common construction, the current of heated air and flame is greatly weakened in its effects before it impinges upon any particular point, owing to the flames taking a longer course in a direct line before they are turned by a bend in the flue, in another direction; but in Messrs. Braithwaite and Ericsson's boiler, it will be perceived (on a reference to the section given in a previous number of the "Mechanics' Magazine") that the strongest flame from the furnace makes a sudden turn horizontally, close above the fuel, and the heat is in consequence chiefly concentrated at the part of the boiler marked a, on which it impinges in the manner of a blow-pipe. Every sensible man must, I think, admit this to be a great defect in Messrs. Braithwaite and Ericsson's arrangement, which is otherwise well calculated for making the utmost of fuel, and in this respect it certainly deserves every commendation. I hope, Sir, should any of your numerous Correspondents do me the favour of correcting any errors that I may have fallen into, that he will have the kindness to put his name to it; because we shall then be able to see if the statements of the anonymous "F," and the "respectable Engineer" in ambuscade, (whom you quoted in the note appended to "F's." letter) meet with any support from PRACTICAL MEN.

I remain, Sir, respectfully, your obedient servant, L. HEBERT.

20, Paternoster-row, Dec. 7, 1829.

[We have before expressed an opinion that it is our respected contemporary, anda ot his opponents, who have taken a wi ng view of this case; and we must

THE BRITISH ALMANAC AND THE COMPANION FOR 1830.

say we see nothing in his present reasoning to induce us to change that opinion. The accident which happened to "The Novelty" is precisely analogous to one of every-day occurrence in common life. Place a copper kettle, with water in it, on a strong fire, and while there is water in it no perceptible injury will ensue. Place the same kettle on the fire, without any water in it, and a hole will be burned through it in an instant. Would Mr. Hebert say that it is the kettle which is in fault here? We do not suppose he would; and yet it is an absurdity of precisely the same kind for which he contends in regard to “The Novelty."-ED. M. M.]

COMPANION ΤΟ THE ALMANAC

JEWISH CALENDAR.

Sir, I thought that you was too hard upon the Society formed for the Diffusion of Knowledge and Encouragement of Literature, by underselling the booksellers, and leaving them nothing to do; but I have now found to my cost that you are right. In the advertisement about their Companion to the Almanac, I saw a little mention of a Jewish Calendar, which I thought I should like to possess. I said to my neighbour, Reuben Cohen, 'Do you think it will be all right, and worth the monies ?'' Fear not that,' replied he is there not a Committee of Superintendence, to which belong Isaac Lyon Goldsmid and Benjamin Gompertz, both true men of our nation; yea, Israelites indeed?" Well, then I bought the Companion, thinking half-a-crown would be well laid out to have all our Feasts correctly ranged in print for the whole year before-hand. But, Sir, I now find, too late, that my monies are gone for nothing, that the Society is not the Diffusion Society, but the Fudge and Delusion Society, and that my two Israelitish brethren have slept at their post. And now, though it be the warning of an indignant brother, let me remind them,that when King Ahab suffered himself to be seduced by false prophets, he was slain at RamothGilead; yea, and the dogs licked up his blood. Sir, will you believe me when I assure you that in the Jewish Calendar, page 31, of the said half-crown book, there are three mistakes, and one feast omitted, in thirty-four lines? These people, Sir, cannot count the number of days in our month Thebeth; they omit our Festival on the 15th of Shebat; they put the 7th and the 10th of Thebeth on

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the wrong days; they put the 1st of
Nisan on a wrong day; and they only
make thirteen days between the 1st and
the 15th. Excuse me, Sir; these people
may make Almanacs for you, Gentiles,
but we, Jews, are not to be thus hum-
bugged out of our monies.
I am, Sir, yours,

NATHAN EMMANUEL.

24 of the month Chisleu, Charles-street, Hounsditch.

THE BRITISH ALMANAC AND THE
COMPANION TO THE ALMANAC FOR
1830.-MR. LUBBOCK'S DEALINGS
WITH THE TIDES.

"The Queen of Night with vast command
Rules o'er the sea and half the land,
And over moist and crazy brains
In high spring-tides at midnight reigns."
HUDIBRAS.

We promised our readers we should return to Mr. Lubbock and his dealings with the tides; and, as the question at issue does not merely involve the scientific capabilities of that gentleman, and the fairness of the strong opinion we have pronounced respecting them, but is one of great interest to all men of investigation, we now hasten to redeem our pledge.

We know not whether Mr. Lubbock was appointed to undertake this recondite inquiry by those who sit in authority at the head of the Knowledge Diffusion Society, and who decree to each

"

his province in the common toil."

Or whether with a spirited determination to outshine Newton and others who have dived into the intricacies of this matter-he comes self-devoted to the task. But in either case the result will be found equally honourable to Mr. Lubbock's intellectual powers, and to the Society in whose behalf he has thus signally exerted them.

We must confess that at first we were thrown into some dismay by the formidable exhibition of mathematical symbols with which Mr. Lubbock makes his advance into the field. We brushed off the dust and cobwebs from Lecroix sur "Le Calcul Differentiel et de Calcul Intégral," determining to surmount all the difficulties which thwarted us twenty years ago, and to show that we too would reduce the tides to our beck, flourish about "integrales indeterminées," "données explicitement ou implicitement." and summon to our aid Taylor, D'Alembert, and Lagrange. But on second thoughts we

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