than we can the essences and modes of being in other instances. It is as much, but no more than other works of God, a mystery to us. So far as into other subjects we can dive into this, but no farther. So far as they are plain, this is plain also. Where mystery begins with them it commences with this-and that is, when we abandon facts and relations, and endeavour to explore essences and modes of being."

OLIVER AND BOYD'S CATECHISMS OF ELE

MENTARY KNOWLEDGE.*

Those Catechisms in this collection, of which it falls within our province to speak, are extremely well drawn up; simple, perspicuous, and attractive. Mr. Lee, the mathematical master of the Scottish Military and Naval Academy, has done great justice to the different departments of " Natural Philosophy;" and Mr. Wm. Rhind to the "Natural History of the Earth, Zoology, and Botany." 'Drawing and Perspective," by Mr. Lawrence, would have been the better of a leaf or two out of Mr. Jopling's "Practice of Isometrical Perspective;" though perhaps the best thing the publishers could do, would be to get Mr. Jopling to furnish them with a separate Cateehism on that important branch of perspective.

66

The Architectural Director. By JOHN BILLINGTON, Architect. Second Edition, greatly enlarged. Illustrated by nearly 100 plates and tables. Part I. Bennet. 1834.

A new edition of a work of standard reputation on the Theory and Practice of Architecture. It is very handsomely got up, and very cheap.

NOTES AND NOTICES.

Steam-Carriage Shares.-The holders are wait ing anxiously the expected appearance of the carriage (which carriage?), and few are in the market. They may, however, be quoted steadyHeaton's at 45, Church's 30.-Birmingham Advertiser, March 29.

The following is an extract from a private letter from Birmingham :-"I dare say you have heard of Dr. Church's no go motive carriage having been tried, and through the carelessness

*Elucidating the more simple Principles of Literature, Science, and the Arts. Neatly printed in 18m0.; with appropriate embellishments by eminent artists." Oliver and Boyd. 1834.

(so reported to me by one of the parties) of the men, the bottom of the kettle was burnt out." Can any of our correspondents furnish us with the particulars of this trial, and the real cause of failure?

Russell's Steam-Carriage.-A new steam-carriage (Mr. Russell's) commenced plying between Glasgow and Paisley on Wednesday. The carriage is attended by a supplementary vehicle, containing the necessary supply of charcoal and water. The carriage itself is superbly fitted up, holds six inside and twenty outside passengers, and is hung upon springs, quite free of the boiler and machinery. The boiler is extremely small, and occupies the space immediately below the carriage, while the boot contains the engines. The boiler is capable of generating steam in twenty minutes. The two engines, fourteen horse power each, sitnated above the hind axle, are connected with it, by cranks working at right angles to one another, so as to produce continuous rotary motion. They are contained in a polished brass box of six cubic feet, and communicate with the boiler in a manner imperceptible to the eye, highly ingenious and quite novel. The whole machinery is poised upon curviform springs of the fourth order, so marvellously adjusted as to prevent any concussion or shock from telling, or taking effect upon the engine; while the potential detachment of the wheel from the axle enables the engineer to stop either wheel at will, and so to turn and steer the carriage according to the most tortuons sinuosities of the road. The bind-axle is alone propelled, and the fore-axle is used as a helm whereby to guide the movements of the vehicle. Hence the wheels, both in the front and back, are at the entire command and control of the superintendent; and although the velocity can be extended up to fifteen miles per hour, it can be governed, regulated, and directed with as much ease as our present mails, and adapted alike to an open country or a crowded street. Weekly Dispatch, March 30.

Roberts' Locomotive Carriage.-Mr. Roberts, of the firm of Sharp, Roberts, and Co., engineers, of Manchester, has been for some time engaged in the construction of a locomotive carriage for common roads, for which he has obtained a patent. One experimental trip was made in December, which, while it led to the detection of a few imperfections in the details, easily removed, has tended to establish the soundness of the principle on which the carriage is constructed. On Thursday the second of these experimental trips was made. The carriage started from the works in Falkner-street at half-past six in the evening, under the guidance of Mr. Roberts, with upwards of forty passengers. It proceeded about a mile and a half up Oxfordroad, namely, to near the end of Nelson-street, where, owing to an apprehension of a deficiency of water, a sudden turn was made. The breadth of the road at this point was insufficient to allow of free scope for the engine, and about six minutes were occupied in making the turn. The carriage then proceeded back to the works, where it arrived without accident just nineteen minutes after starting. The maximum speed on a level was twenty miles per hour, and the acclivities of the road were mounted without the least sensible effect on the speed. No doubt exists of the engine being speedily put in complete and effective condition for actual service.-Manchester Advertiser, March 29.

A nice little World.-The diameter of Pallas does not much exceed seventy-nine miles, so that an inhabitant of that planet, in one of our steamcarriages, might go round his world in a few hours.-Mrs. Somerville.

There was a grand exhibition of the Thames Tonnel last week to a number of members of the

Royal Society, and distinguished foreigners, "for the purpose," say the newspapers, of inspecting this extraordinary undertaking, and of considering the practicability of the completion of the work," when every body present was perfectly satisfied that it could be completed with ease, and that it is a prodigious "reproach to the country," the funds necessary for the purpose are not forthcoming. A "reproach to the country," forsooth! We wonder whether it was explained to the distinguished foreigners who were present, that the country came forward with every farthing of the money which the engineer calculated to be requi site for the complete execution of the Tunnel; and that the total loss from the irruptions of the river, to which the stoppage of the work, about half-way is so conveniently ascribed, did not exceed 13,000l. The undertaking is at a stand, simply because it cannot be completed for donble the engineer's original estimate, and because, if completed at such a cost, it would not, in all probability, yield a shilling of revenue to the proprietors.

Navigation of the Danube.-An important project is on foot for establishing a regular communition, by means of steam vessels, between Vienna and Constantinople, and, at some inture period, in connexion with that project, a communication with the German Ocean and the English Channel, by means of the Rhine and the rivers which connect it, or nearly so, with the Danube. On the part of the Austrian government this affair has become, in some measure, a state object, and great numbers of the Austrian nobility, and the sovereigns and nobility of the contiguous German states, have embarked money in it. The project is not altogether a new one, a company having been formed (query, projected only?) in the year 1830, under a charter from the Court of Vienna, for the navigation of the Danube within the Austrian dominions, with which the present undertaking will naturally connect itself, and become an extension of it. The first object will be to establish the intercourse, by steam vessels, between Vienna and Constantinople, a distance of 1500 miles, and the estimate is, that this may be accomplished in ten days, allowing the vessels to come to anchor during the night; but that, when all the arrangements are completed, it is supposed that the voyage may be performed in seven days. Preparatory surveys made of the course of the Danube, by order of the Austrian government, are said to have afforded satisfactory proof that few natural obstacles exist, and those few easy of removal.-Times, City Article. The following additional information on the subject is extracted from the Parisian private correspondence of the Times:-"The only local difficulty, which has long stood in the way of the project, consists in a rocky part of the Danube, extending all along that river from Orsova to Ada Kalé, a distance of about twenty-five English miles. very enterprising and wealthy Hungarian nobleman, Count Seczini, who has an estate which borders that part of the river, had for several years been at vast trouble and expense in trying to find some mode of dislodging the rocks, but he was compelled to give up the hope of doing so, though not of ultimate success in the object he had in view. A canal has been commenced, at his expense, over his estate, by means of which the rocky part of the river may be avoided altogether. This canal will serve the double purpose of avoiding the rocks and the distance formed by a circuitous direction that the river takes where they are situated. The canal was only commenced about three or four months ago, and will not be completed until next year. Hitherto the steam-boats going down the Danube started from Raab, in Hungary, a town situated half-way between Presburg and Buda, and proceeded only as far as Orsova, be ing prevented by the rocks from going farther."

A

Count Seczini (Cznecki ?), the Hungarian nobleman mentioned in the last extract, is now in Loudon, for the purpose (we believe) of procuring information connected with the prosecution of the undertaking in question.

A Correspondent at Boston (U. S.) informs us that Mr. Rutter's new mode of generating heat from coal-tar and water has been adopted at the gas. works there with great advantage. The proprietors have followed, without deviation, the process set forth by the patentee in his specification, and first published in our Magazine of the 14th September last.

"An Attentive Reader of the Undulating Controversy" proposes that a sum of money should be staked on the result of a trial of an undulating line. He requests us to ask, "Whether Mr. Badnall and Mr. Cheverton have confidence enough in their respective opinions, to come forward singly, or sup ported by their friends and advocates, and stake a sum of money on the event?" He for one, he adds, "would be happy to back Mr. Badnall." The wager, our correspondent suggests, might be laid so that "the winner should pay for the expense of the trial; which expense, in case of failure, would be merely that of laying down the rails and taking them up again, on any projected line." The sum he names is from 1,000l. to 2,000l.

John Fuller, of Rosehill, Esq.,-" Honest Jack Fuller" (sometimes "Eccentric Jack"), as he used to be called, before he abandoned the turmoil of political life for the quiet retreats of philosophybefore he gave up lecturing Speakers, and took to founding lectureships-has, besides establishing the Fullerian Professorship of Experimental Philosophy in the Royal Institution, now so ably filled by Dr. Faraday, lately invested a sum of 3,3331. 68. 8d. three per cent. consols, for the endowment of a Professorship of Physiology in the same Institution; and another sum of 3,000l., three per cents., to form an accumulating fund for the general purposes of the Institution. The total amount of this gentleman's donations to the Royal Institution falls now little short of 10,000l. The members have testified their grateful sense of this extraordinary instance of munificence, by voting that a bust of Mr. Fuller shall have a distinguished place in the Library of the Institution. So much, some will say, for pelf-which exalts a mere country squire to the same honours as a Rumford and a Davy. Far be from us, however, so narrow a measure of justice! We say, on the contrary-so much for great wealth nobly and usefully employed; and may the admi. rable example of Honest Jack Fuller" have many imitators among the squirearchy of England!

Communications received from Kinclaven-Mr. Badnall--S. P. A.-A Shareholder-Why so?Mr. Erpingham,

PORTABLE AIR-STOVE AND VENTILATOR.

Sir, Having personally had painful experience of the evil effects of want of due ventilation in crowded workshops, more especially where particles of metallic dust are flying about, and stealing their way into the lungs, I am induced to send you a plan of a portable air-stove and ventilator, by the use of which in such places the atmosphere may at all times be kept perfectly pure and wholesome. I showed a working model of it, about three years ago, to an eminent physician, who thought it would be equally applicable to hospitals, lazarettoes, &c., and that it might be introduced there with very great advantage.

The lower figure exhibits an elevation of the apparatus, on a scale of a inch to a foot; and the upper one a crosssection, on a scale one-third larger.

A is a common cast-iron stove, such as is used in laundries, &c. The fuel may be either coal or coke. The heated air, &c. rises into an inner wroughtiron cockle marked G, whence the smoke escapes through the pipe or opening H. This cockle has an outward casing 1 I, of about 4 inches in diameter, round which a stream of air is driven in the direction indicated by the arrows, from the fanner B, and issues in a warm state at the mouth of the pipe K. There are two shutters JJ, on each side of the cockle, to compel the stream of air to pass over the top of the cockle. LLLL is an iron frame, which supports the cockle, and contains the fanuer. PP are doors by which to clean out the cockle occasionally. QQQ are stays, or supporters to the cockle. R is packing or false bottom, to prevent the radiation of the heat. D and C are the wheel and pulley-sheave by which the fanner is worked. They may be turned by hand, or any other convenient power, at the rate of from 200 to 250 revolutions a minute. M is a pipe, by which a supply of cold fresh air may be conveyed from the outside of the building to the fanner. The whole apparatus may be placed on a wooden frame, with only a few bricks for the stove to rest upon.

The large brick air-stoves, invented by that eminent mechanic, Mr. Strutt, of

Derby, are on the same principle as the present. We have six of these at work at the mills where I am employed. I only claim the credit of making them portable, and all of sheet-iron, except the wooden foundation and wheel.

Such portable air-stoves would be particularly serviceable to architects, builders, &c., and might be lent for hire for 4s. or 5s. a day, in the same way as engine-makers are in the custom of letting out their copper pumps to well-sinkers. I remain, Sir, Your obedient servant, WILLIAM REED.

Imperial Paper Mills, Peterhoff,
New Year's Day, 1834.

THE AMERICAN PRACTICE OF WORKING THE ENGINES OF STEAM-VESSELS SEPARATELY.

We extract the following interesting information, on this head, from a letter of Mr. Armstrong, the captain of the "John Bull," which plies between Quebec and Montreal, to Nath. Gould, Esq., Deputy Chairman of the North American Land Company, published in the Nautical Magazine:

"The arrangement is simple, and depends entirely on the separation of the two engines; one of which drives the wheel, and between which there is no connexion whatever; except that in general both boilers are connected with the steam-pipes of each engine, in order to equalise the supply of steam. It will be clear to you that, under this arrangement, either engine, and consequently either wheel, may be worked a head, reversed, or stopped, independently of the other. This mode of applying the power of steam is entirely different from that adopted in England. There the feeling in favour of the connexion of the two engines is so strong, that the remaining engine is considered as nearly useless after its partner is disabled, whereas no inconvenience has yet been found here to result from the want of the connexion. Each engine works as easily, and passes the centre as well, as it could do if connected with the other, and may be stopped or reversed while the boat is under full speed, without any difficulty or danger. 1 may compare the steamer to a small row-boat with two oars, one backing and the other pulling, and vice versa, or both forward or both backward, as the occasion may require. The advantages of this arrangement in a

tow-boat, when getting under way from a wharf, or in a crowded port with vessels in tow, can hardly be too highly estimated. The boat can literally turn round and round in her own length, and the manœuvre is performed here daily. Nor is it in river boats only that this plan is adopted. On Lake Ontario, and in the boats passing through Long Island Sound from New York

to Providence, it is universal. On Lake Ontario, the sea is particularly short and trying to a steamer, yet the "Great Britain" is now running from Prescot to Queenston, for the third summer, without having met with any accident, although she carries her boilers on deck, and although her two engines, of 80-horse power each, are perfectly unconnected."

m

1.

Sir,-The arrangements represented in the above figures will show that the steam-boat machinery, described in Number 513 of the Mechanics' Magazine, may be still further simplified, and put up in a more compact way, than it is there represented.

Fig. 1 shows the line of shafts running across the vessel; fig. 2 is an end-view of the same. In fig. 1, aa and b b are the short shafts, with two cranks on each, that work on the top of the cylinders; the cranks on a a are set at right angles to the cranks on b b. The shaft c drives the one paddle, and the shaft d works the other; ee and ff are the perpendicular lines passing through the centres of the cylinders; and the lines g, h, i, k, mark where the connecting-rods work; Im is a bolt, with a nut and ruff at each end, for connecting the pin of one of the cranks on the shaft a a with the pin of the crank on bb, that is next a a. By connecting the shafts in this way, we get quit of the intermediate shaft, with the two cranks on it at right angles to each other, for connecting the two engines, and also of the framing-work which supports it; and the engines take up less

Fig. 3 is a diagram, showing the positions of the lines passing through the centres of the cylinders parallel to their sides, in the second plan; and is a more compact and simple arrangement than any of the preceding. Let a be the centre of the shafts, then a b will show the direction of the line passing through the centre of one cylinder, and ac will give the position of the centre line of the