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63 ment? Luckily, Dr. Dalton's theory Professor Graham say of this "mechathus explains this apparent anomaly, ac nical separation,” thus attributed to his cording to Mr. Armstrong's new version; idea of the “tendency of gases to diffuse for he would prove, that the smoke and into each other?" unconsumed combustible gases, after But, lest any doubt should remain on having passed round the boiler, and the subject, we are told in plain English, being intermingled and diffused, under “it is precisely this separation," (after the Daltonian theory, are, by the magic the previous diffusion,) “that is effected peculiarity of a fan, and at the very same by Mr. Cheetham's process." How far Mr. time, separated, (as chaff is from wheat,) C. may feel obliged to his eulogist, for this the useless and incombustible gases alone explanation of the process, I leave to him passing up the chimney, while the combustible portion, thus miraculously sepa Now, the ingenuity of this philosorated under this diffuso separative pro- phical diffusion-separation process recess, returns again, (under said squirrel minds one strongly of the philosopher, system,) to the ash-pit, furnace, flues, (Swift's, I believe,) who suggested an and boiler. Thus we find that Dr. Dal- equally ingenious mode of producing a ton's theory of the intimate intermixture diffusion of talent and temperament in and diffusion of gaseous bodies without the human species. His plan was, the reference to their respective specific gra taking a slice off the brain of the sanvities, (long since admitted to be correct guine man, and exchanging it for a slice by the whole chemical world,) is now, from the brain of the phlegmatic—thus by the new light chemistry of Mr. Arm- virtually reconciling diffusion with sepastrong, discovered to possess the addi ration. Equally ingenious, and equally tional peculiarity of separating the com practicable and valuable, is this with Mr. bustible from the incombustible gases, Armstrong's separation-diffusion theory. just at the moment when, by the same (To be concluded in our next.) faws, they had become intimately diffused among each other. To this, however, must be added the peculiar action of a fan,

PECULIAR CASE OF OXYDATION. which, also acting in a double capacity, propels the useless gases up the chimney, and

Sir,— Will you permit me, through sends the useful ones round again to the your pages, to ask advice of some of your furnace! Who will hereafter despair of

readers under the following circumimpossibilities?

stances : Mr. A. observes, “your chemical

I have a carpenter's stove for steaming readers " (doubtless he ihought it was plank in, which, when fully exposed to too profound for mechanical ones,) "will ihe atmosphere, I found the steam to be aware that this circulatory process

condense so rapidly, as very much to cannot go on without atmospheric air, lessen its utility. To counteract the and which air is admitted by a small speedy cooling I had it cased with plank aperture between the fan and the smoke on the outside of the flanges, by which flue." How this small aperture can ad its separate pieces are secured together, mit 360,000 cubic feet of air for each ton and the space between, say 2 inches, of coals, the theory sayeth not.

filled with sawdust: this effectually preMr. A. observes, " It was demon vented condensation, and, as I fancied, strated by Dr. Dalton, that different answered my purpose; but on renewing gases act as vacua to each other, while a part of the casing after six months use, Professor Graham has shown that the I found the stove rusted to th, or upwards, different gases have a tendency to diffuse

of an inch, and the decay apparently into each other with different degrees of going on. Now, at this rate, it will very rapidity, which bears a certain relation soon be holed through, and if some of to their specific gravity; and hence he, your correspondents would, through the (Professor Graham,) shows that, by

Mechanics' Magazine, favour me with availing ourselves of this tendency in advice, they would much oblige, mixed gases, a sort of mechanical sepa

Your obedient servant, ration of the various gases may be ef

A Constant READER. fected." Here is a flight of philosophic Glasgow, January 13, 1842. ingenuity, with a vengeance! What will

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Sir,- If you think a description of the a small shoulder at e, where the seat-iron little vehicle named and sketched above f works on it, and a thumb-nut at the worthy of a place in the pages of your top, to secure the handle g. Magazine, it is at your service.

The seat-iron is of full k-inch round I will only premise that I have made iron, flattened at the seat part; and the one, and found it to answer extremely seat, which is of the shape shown in fig. well.

2, is covered with cloth, and stuffed: a, figs. 1 and 3, is a piece of board, i There are spring keys at e and the point in. thick, 4 in. wide, and 18 in. long, of a. The height from the ground to e made of the shape shown in fig. 3. is 2 ft. 4 in.; from e to g, 10 in. : the

b b, two runners, made of steel, 1 in. weight of the whole is under 12 lb. thick, 2} in. wide, 11 in. long, screwed The method of using needs no descripto the sides of a.

it being only necessary to wear c, the front runner, 1 in. wide, 10 in. coarse worsted hose over the boots, to long, turned up in front like a skate, and

prevent the feet from slipping on the slightly curved at the bottom edge. d, a rod of 3-inch round iron, made

I am, Sir, with a clip at the bottom, by which it is

Your obedient servant, attached to the runner c; it works in a

J. R. hole at the point of the board a, and has Hastings, January 10, 1842.



THE CAPOR DEFLECTOR LAMP, COMMONLY CALLED THE SOLAR LAMP. Sir, — Messrs. Timothy Smith and position, namely-does the cap or deSons, of Birmingham, have, it appears, Rector, which is the sole distinction beunder the pretence of replying to the tween the Solar and other lamps, make a statement of “A Constant Reader," in prominent feature in the expired patent troduced my name, telling your readers of Upton and Roberts ? I assert it that they have commenced an action does ; and, in proof, refer to the specifiagainst me, for selling a patented inven cation of that patent, in which two lamps tion of Mr. Young's, which they please are described, by drawings and in words, to term an infringement of the patent of both having caps or deflectors identical Mr. Jeremiah Bynner. As this assumed with those used with the Solar Lamps. important intelligence has really nothing The lamps are Nos. 4 and 9, and the to do with the matter in dispute, and was specification is at the Petty Bag Office, evidently intended to divert inquiry from where it can be inspected by any one. its proper object, I trust you will permit A great number of the lamps referred to me to keep the point at issue in its right were made and sold during the term of


65 the patent, from 1827 to 1841. Many An increased volcanic action, (aurora of them are now in use, in various parts borealis,) has been occasionally observof England, and can be produced to able at the north pole for a length of Fouch for themselves. Besides what has time. This has, of course, occasioned a been stated, there is that which will, no great disruption of ice, and consequent doubt, be considered rather a peculiar approach of it towards the equator, the feature in the case. Some hundreds of evaporation of which has filled the atmothese lamps were made, in virtue of Upton sphere with moisture. By the volcanic and Roberts's patent, by Messrs. Timothy action of the 25th of September, the Smith and Sons, under the superintend- overloaded metallic fluids were shaken, ence of Mr. Jeremiah Bynner, who was and the additional moisture has been then acting as the foreman of Messrs. coming down ever since, like the dripSmith's Lamp Factory, and this was at ping of an over-saturated sponge. It is least two years before he obtained his not during the commencement of the patent. This is rather a startling fact, derangement of the system that the pulse and will surprise those who know what is the most affected, but at the crisis of has to be done to obtain a patent, whether the disorder. The liquid that is tranquil told in your pages, or reserved for a in the half-filled cup shakes on the brim. court of law.

There can be no doubt that the sky, (the What I have here stated, Sir, are upper region of the atmosphere,) is the facts, which I am prepared to substan emporium of metal in a state of sublimatiate ; they are facts which concern the tion, or of electricity. To this metal public, and give the free and immediate moisture adheres. Look at a flake of use of these caps or deflectors to every snow—what else gives it its star-like one. If Messrs. Smith are desirous of form, with its serratures? I know not making a statement, let them make one whether the geologist has ever thought which will meet the point at issue. If of tracing his metallic veins to the skyactions at law are cited, let them be de if he have not, behold a theory for him, cided ones. The public are not, they worthy of his deepest consideration. I may rest assured, to be hoodwinked by have another theory for him, on the subreference to an undecided action, which ject of coral rocks. All in good time. proves nothing, and may end, as such affairs not unfrequently do, in stripping authority from whom the prefixed motto is

“ In the next place,” says the same learned a doughty assailant, like the ass in the

taken, "we may venture to say, that adfable, of the lion's skin.

vances in knowledge are not commonly I remain, Sir,

made without the previous exercise of some Your obedient servant

boldness and science in guessing."-Vol. i.

GEORGE Upton. Oxydator Office, 33, George-street, Hanover-square.

A blunderer is better than one who January 11, 1842.

cannot guess at all, and who rests satisfied with not knowing. I took it into my

head, the other day, to place a great U THE LATE MAGNETIC DISTURBANCES.

before things unknown. What a number " In the advance of knowledge, the value

of U's! How many which there is no of the true part of a theory may much out

chance of expunging, while it is believed weigh the accompanying error; and the use

that matter can continue to move without of a rule may be little impaired by its want

a continuous force. Great a man as of simplicity. The first steps of our pro

Newton undoubtedly was, " in sweepgress do not lose their importance because ing the skies," he resembled “Dame they are not the last; and the outset of the Partington," or the silk-merchant who journey may require no less vigour and ac wanted to have all the silk-worms' eggs tivity than its close."-Whewell, Hist. In. destroyed, because he found some moths sec. i. p. 118.

amongst his cocoons. What had a moth's Sir,—The remarkable magnetic dis egg to do with silk ? I have lately been turbance at the Greenwich Observatory told, that much of what I have brought had engaged my attention previously to forward is not new-that it was known your announcement of it in your last to the ancient pagans. I know that: I Durber.

know also that it is known to the pagan:

p. 411.

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of 1842. What of that? Do we not ing engine. I beg to offer a few observaeat, drink, and sleep, as the pagans did, tions on that part of it which appears to and do? Why should we not think as me most open to objection. the pagans did, and do, in matters that Mr. P. I think, overrates, in the first do not interfere with our faith? It is place, the perfectness of his vacuum as just as absurd to think people are wrong compared with that of the common enin all things, as right in all things. The gide. He says, speaking of the condenser part of my Theory of the diverse* which of the common engine, that “all air and I believe to be new is, that of the absorp gas cannot be withdrawn at each stroke tion of a universal Huid being the cause of of the air-pump; half, at least, must the approach of solids to the earth-that rerrain in the separate condenser, which the opposing currents of air are the cause will expand and make the extreme vaeuof the approach of bodies without absorp um less by 1!b." One might almost tion—that there is positive cold, consisi be led from this to suppose, that Mr. P. ing of separate atoms, in a peculiar Huid- meant to say that all the air and gas given and that positre heat is a globular ar out in the last condensement cannot be rangement of the said atoms with the withdrawn at one stroke of the air-pump, said Huid, the change being wrought but that a portion of it remains to vitiate through the medium of vegetable and the vacuum. Bat what must be the inanimal existenee, and thai the continuande evitable result, if such were the ease? of all motion is due or caused by lite. Certainly this, that the air-pump being If this has all been made known before, unable to withdraw all the air and gas I suppose the objection is also known. given out at each condensement, that What is it?

portion which is not so withdrawn, or reI pretend to no more than a wish to mains behind in the condenser, must make others see the beautiful view which continue to accumulate until the vacuum I have seen. If any one is afraid of a become thoroughly vitiated. Mr. P. * chamois-bunt," as Coleridge calls fol. must perceive that such must be the relowing a deep thinser, he can but turn sult on the supposition stated; but as back. I do not dispute the foree of the no sueh incremental accumulation of attraction of a good fire, an easy chair, gases takes place in the condenser of the and a book. Go back. Woen Socrates common engine, it follows that the airwas asked what he thought of the theories pump does in fact withdraw all the air and of Heraeiitus ? he repiied, that " what gases given out in each condensement. he understood of them he found so à certain portion of air or gas no doubt clever, that he concluded what he did always remains in the condenser, aris. do: understand was so likewise." There ing from the unlimited expansibility of is a precedent for all poissophers. At gaseous bodies, and the consequent imany rate, be did not condean what he possibility of any air-pump, however did not comprehend.

perfect, completely extracung it from a In a former number of your Maga- chamber which is own piston does not zine, my attention was drawn to the sub- fill, and in which, therefore, it will find ject of the growth of trees. Is it attrac room to expand. It may, honerer, be attion that lifts those enormous masses tenuated to a certain point, and there is noabove the earth? Yes-capillary attrae thing in theory or practice, except in as far tion! What is capillary attraction : as arises from imperfection in construction, Something very different from any ae. to prevent the air-pump of the common enunt of it that I have as yes seen, or I engine maintaining the vacuum ai that am much mistaken. Of this at ano:her limit

. As the pision of Mr. P.'s conopportunity.

denser fils or traverses the whole internal I remain, Sir, your obliged, &c., space or chamber, it certainly expels

E. A M. every portion of air or gas from within, Jancary 15, 1842.

and his condenser is therefore free from

the imperfection just adverted to in the M2. PILBROW'S CONDENSING ENGINE.

condenser of the common engine; but it ST.-As Mr. Pilbrow has invited dis.

does not necessariis follow that in praceussion on the merits of his condens.

tice de ovtairs a beiter vacuum than that

of the cominon engine ; for there is an• Sec Neck. Mag., vonviv. and xxxv. other consideration to be taken into ac


PILBROW'S CONDENSING ENGINE. count, namely, the difference in size or quantities equal! The air-pump of the capacity between the two condensers, and common engine is made of definite prowhether the vacuum in bis comparatively portions, to effect a definite end-the exsmall condenser may not be as much vi. pulsion of the gases and water which are tiated at the end of each condensement as found in the condenser at the end of each that of the common condenser, which is not condensement; and that proportion is limited in capacity like Mr. P.'s. Take given to it which is just suitable to prothe state of the two condensers at the end duce the result intended, and not more. of one condensement; and just before

The size of Mr. P.'s air-pump, or the the engine makes a new stroke. The area of his condenser piston, (which is vacuum of the common condenser is the same thing,) is not made with revitiated by the gases given out during ference, primarily and only, to the purthe condensement just concluded, the pose of ejecting the gases and water revapour due to the temperature of the sulting from each condensement, nor has condensements, and that constant portion it those proportions which would be given of gas which the air-pump cannot with to it, if it had merely that end to fulfil. I draw; but then these are diffused in a cannot acquiesce in Mr. P.'s reasoning, large space or chamber. In Mr. P.'s that a large area of piston and short condenser-the vacuum is vitiated in like period of discharge necessarily come to manner by the gases given out during the the same thing as a small area and a long condensement just finished, and by the period of discharge, which is the infervapour due to the temperature of the con ence deducible from his words in the densements-being free, however, from quotation. I have given. Enlarging the the constant portion of gas of the com area of the piston does indeed defer and mon condenser ; but then they are

shorten the period of discharge; but, cooped up and confined in a small or however much the area may be enlarged, limited space; and it may be worth in a time must come, though it be at the quiring whether, under these circum very end of the stroke, when the constances, their elasticity, or power of offer densements must be discharged, and the ing resistance to the piston of the engine, pressure of the atmosphere let in on the is not as great as in the common con piston : yet I can hardly think that Mr. denser, or, in other words, whether in P. will assert that the total amount of practice his vacuum is at all more perfect pressure on the piston is still the same. than that of the common condenser.

There are two things which, it appears The main objection, however, to Mr. to me, Mr. P. has not satisfactorily P.'s engine, and which will more than proved, and I submit them to his candid counterbalance any advantages it may

consideration, have in other respects over the common

1. That the total amount of pressure engine, is, the enormous resistance to or resistance from the atmosphere on his which it is subjected, towards the end of condenser piston is the same as, or not each stroke, by the pressure of the atmo greater than, the resistance of the same sphere on such a large surface as the fuid on the piston of the air-pump. of area of the condenser piston-a resistance the common engine—the steam cylinders which, added to the work performing by of both engines being in all respects the engine, may well nigh go to stagger

alike. and paralyze its movement.

I am un

2. Supposing the amount of pressure able to perceive the soundness of Mr. of the atmosphere to be the same in P.'s reasoning on this point. He says,

both, whether the accumulation of this “No enormous burden thrown on my resistance at the end of the stroke, when engine, not an ounce, whether the con

the crank is in the worst possible posidensement is thrown out by a large area tion to carry on the movement of the of piston and a short period of discharge, engine, is not far more prejudicial to its (as in my engine,) or by a small area of effective working, than the same resistpiston and a long period of discharge, ance diffused over the whole, or a con(as in the present engine,) the total effect siderable portion of the stroke. of the pressure of the atmosphere must

N. N. L. be the same, the quantities being, as they

January, 1842. will be, equal." In what respect are the

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