and the other rooms are for paintings executed by means of fire; such as glass, porcelain, enamels, &c.

What is the greatest height of your rooms in the gallery of paintings; what is the height and width of the largest picture they would contain in English feet?-The rooms of the principal floor are 52 feet high to the top of the vaulted ceiling, 314 feet to the springing. The width 42 feet. The principle upon which the several dimensions were regulated, in consultation with the director of the gallery, was this:-All the pictures are fixed upright against the wall, not sloping. The highest point at which the top of the largest pictures should be placed was assumed to be 29 feet, the lowest 4 feet. The shortest distance from which it should be seen 25 feet.

Does any person reside in the building?— No person is allowed to reside in the building for fear of fire.

Is the building fire-proof-It is entirely fire-proof. All this gallery is heated with warm air, in order to preserve the pictures from humidity, which very essential for the preservation of the paintings, and more particularly in such a climate as this of England.

Should the temperature be always the same?-As much as possible; in winter the temperature should never be less than ten degrees of Reaumur.

Have you not also several provincial galleries in Bavaria ?-Yes; we have three at present, at Augsburgh, Nuremberg and Schleissheim, and they are going to establish several others in other principal towns.

All those galleries are open to the public without any payment? Yes, it is open to every body. It is most expressly prohibited to take the least payment.

Do you think it is desirable in a picture gallery to put over the different schools the name of the school, and upon each picture the name of the painter and the time when he was born and died, and perhaps the name of his master?-Certainly.

Have you also a catalogue raisonné ?— We have; that is quite necessary.

Have not you in Bavaria what is called Kunst-vrreinse, or associations which purchase works of art, and dispose of them by lottery to the contributers of the lottery?We have. Those galleries are open all the year round, and they act as a very great encouragement to art in that branch which does not receive the patronage of the Government, which is of course confined to pictures of the highest class.

SUGGESTIONS ON AERIAL LOCOMOTION.

Sir, It is remarkable, that while the art of directing balloons is acknowledged

to be such a desideratum, that so few experiments have been tried towards effecting it.

To attach oars or wings to the car must be inefficient, because the balloon draws the car (as well as keeps it up), and not the car the balloon. All the propelling power, therefore, that can be thus gained, will be uselessly expended, as the car will never get a-head of the balloon.

I would propose, then, that two light and ample wings be connected with the balloon to a strong hoop, with valves admitting the passage of the air in their backward motion. Two poles or bowsprits can be projected "fore" and “aft” of the car, with pulleys at the ends; and by two ropes fastened to the wings near the hoop, and running through the pulleys, a reciprocating action can be produced, which will enable the balloon to move with a somewhat greater celerity than the current, and in proportion to the relative speed thus gained, will be the advantage derivable from the rudder.

Nature is generally the best guide. It may be desirable to keep in view the action of a bird, remembering that art gives us an advantage, by rendering unnecessary the immense muscular power required to keep the bird buoyant, the gas answering that purpose.

To oppose the wind, of course, will ever be impracticable; but I doubt not that a few trials will suffice to adapt the principle already unsuccessfully attempted, to the purpose so generally desired, so far as to allow of a deviation of one or two points from the wind's direct course.

The mode adverted to by a former correspondent, of connecting birds with the balloon, appears to me well worth experiment. If attached to the frame in such a way that they must fly in one direction, that direction would of course be regulated by the rudder, and training rendered needless. I wish Mr. Green or Mr. Graham would avail himself of the opportunity which the liberal proprietors of the Zoological Gardens would doubtless present them with, of borrowing a few eagles to try it partially. The balloon, however, not the car, must be primarily drawn.

I am, Sir,

Yours respectfully,
WM. RANWELL.

Woolwich, Nov. 22, 1836.

169

B

Sir, With this you will receive a drawing representing an improvement in the water-wheel governor, which, having tried and found it to answer, I can confidently recommend for the adoption of such of your readers as may have the superintendence of water-wheels where a steady and uniform motion is required. The difficulty of making a water-wheel governor to act well, is known only to those who have, in the course of their business, been called upon to fix one to a wheel where an irregular action is a necessary consequence, from the nature of the work which the wheel has to perform. But, independent of any irregu larity in the resistance which the wheel has to overcome, the wheel itself is extremely liable to get out of balance from the unequal absorption of water by the different parts, and other causes, which renders it extremely difficult to adjust the governor, so that the machinery shall

work with a uniform motion. To obviate this difficulty, I introduced the counterweight and bridles, marked A and B in the drawing, which entirely neutralizes the evil effects produced by small and unavoidable inequalities in the balance of the wheel, arising from the unequal absorption of water by the different parts. So decided an effect was produced by this small improvement, that for upwards of two years the governor maintained a uniform command upon the velocity of the wheel without requiring any adjustment whatever; and I have been informed, that this plan has been adopted at several manufactories in the west of England. When any portion of the resistance is removed from the wheel, the governor acts as in ordinary cases, whilst, at the same time, the improvement here recommended checks the evil arising from small irregularities.-Yours, &c. HYDRAULICUS.

In our last year's notice of this almanac we were induced to recommend it strongly to the attention of our readers, from a conviction of its peculiar adaptation to engineers and mechanics-to every person, in fact, in any way connected with mechanical or engineering operations. As every thing connected with the advancement of mechanical science claims our special attention-so, in like manner, wherever we perceive a disposition, as in the present case, to recognise the important station which the mechanic holds in the body politic, we are at all times ready to concede our meed of approbation, cheerfully and cordially. That the present wealth, greatness, and political status of England, is to be attributed to the pre-eminent skill and industry of her artisans and mechanics, is as plain and incontrovertible as any axiom in Euclid. The Inventors of Britain-these are the true nobles of the land, the best benefactors of their country. "Nelson and the Nile"-" Wellington and Waterloo"-may be sounds agreeable enough to martial ears; but to those who delight to cultivate the arts of social life, who rejoice in the contemplation of whatever adds to our store of pure and peaceful enjoyments, "Watt and the Steam-Engine". "Arkwright and the Spinning-Machine". are associations that will ever recur to their minds with much deeper and livelier feelings of gratitude and veneration. The engineers and mechanics are the true bones and sinews of the nation. As a body, they

are possessed of a larger amount of sound, practical, and productive knowledge, than any other body of men in the whole world. And to revert to our more immediate theme-the Mechanics' Almanac— we would say, as the highest praise we can bestow, that it is in every respect worthy of the body to whom it is addressed.

A simple enumeration of its principal contents will show that this is not unmerited commendation. Opposite to the usual calendar pages (in which the times of the sun's rising and setting for every day are given, as shown by a well-regulated clock or watch, and not according to solar time as before-a judicious change) there are historical and biographical reminiscences of each month, culled principally from the annals of invention and diseovery, and likely to be of a most usefully suggestive character to the minds of mechanical readers. quote an example or two :

We

"3 (Jan.) 1795.-Josiah Wedgwood died, aged 65; born July, 1730; the great improver of the English pottery manufacture. "He converted a rude and inconsiderable manufacture into an elegant art, and an important part of national commerce. By these services to his country he acquired an ample fortune, which he blamelessly and reasonably enjoyed, and generously dispensed for the reward of merit and the relief of misfortune."

"28 (March) 1380.-Gunpowder is supposed to have been first used in Europe by the Venetians upon this day. About the time that printing was invented, by · divine

inspiration,' says Rabellais, as a set-off against the Devil's suggestion of artillery.'

9 (April) 1788.-The first threshingmachine ever in use was secured to Mr. Andrew Meikle, of Houston Mills, near Haddington, Scotland, its inventor, by Letters Patent of this date. Being at Kilbagie, the residence of a Mr. Stein, Mr. Meikle agreed to erect a threshing-machine for him, in which the grain was beaten out by the drum after passing through two rollers, used for drawing the grain into the machine. This machine was completed in February, 1786, and being found to answer its intended purpose with a few improvements, a patent was applied for, and, after considerable opposition, obtained."

Following these Reminiscences, we have Astronomical Phenomena of 1837Explanation of the Equation of TimeTable of the Illuminated Portions of the Dises of Venus and Mars-Best Criterion of a Good Telescope-Evenings and Selections favourable or otherwise to Astronomical Observations-Powers of Telescopes necessary for Observing various Celestial Bodies-Note on the Satellites of Jupiter-Friendly Society Tables (an excellent selection from Mr. Ansell's valuable Treatise on Friendly SocietiesTable showing the Proper Number of Turns or Twists to an inch of Cotton Warp for every Degree of FinenessNew Patents granted in 1836-List of Patents which expired in 1836–Rules for Estimating Water-Power-Comparative Value of Building-Ground in and about London-Comparative Cost of Buildings (per Square) in London— Comparative Table of the different Modes of Expressing the Pressure of SteainTable of the Weight of Plates of differeut Metals-List of Alloys, Solders, and Amalgams, used in the Arts-Tables of the Number of Woollen, Cotton, and Silk Manufactories in the United Kingdom, and of the Number of Hands they Employ-Table of the Number of PowerLooms in the United Kingdom; after which come various lists and tables not of so rare and peculiar a character as thr preceding, being such as are, more oe less, common to all almanacs-from tables of heads that wear crowns, to tables of heads that wear hair-powder-the number of which last, we are rather startled to observe, amounts, with all our improved notions of the proper use of heads, to no less than 10,512.)

This is an almanac which appeared (we believe) for the first time last year; and we rather take shame to ourselves for having allowed a year to go bye without giving it that hearty welcome which the usefulness of its purpose, and the good judgment with which that purpose has been worked out, deserved at our hands. Of the various class almanacs, into which the increasing intellectual wants of the community have caused this branch of the book-trade to be subdivided, this is, in our humble opinion, one of the very best. If we may except the Mechanics' (and perhaps our mechanical relationship does not qualify us to be the most impartial judges in the world of the merits of that particular production), it is by far the most readable annual of the kind. The articles in the present year's edition, intituled, On Making a Will-Hints for the Mistress of a Family-On Fires and Fire-Establishments-Miscellaneous Hints and Directions in Domestic and Rural Affairs-Parish-On the Means of Preventing Offences-Short Explanations of such Law Terms as occur in Newspapers-Causes of Bankruptcy-are all extremely germain to "Family and Parochial" matters, and well worth reading and remembering by every head of a family or parish. There is one article " on the British Constitution," in which a higher flight is attempted than in any of the others, but by no means with proportionate success. It seems to us, in fact, not only out of place, but not fitted for a good place any where. The writer thinks the genius of the British Constitution is penetrated by a repetition of the old dogma, that it is a balance of power resulting from the resolution of three different forces, the King, the Peers, and the People; whereas, the most enlightened of our recent constitutional writers are agreed in opinion, that this so long received dogma is but a plausible fiction, in direct opposition to experience and common sense, which are every moment bearing proud witness that in the scale of national interests, the influence of both Princes and Peers weigh, and ought to weigh, but as a feather against the Will of the People.

Whatever difference of opinion may exist amongst the witnesses examined as to the extent of the danger to be apprehended from fire caused by locomotive-engines upon railroads, the Committee are satisfied that, unless due precautions are systematically adopted, the danger would be considerable, not only in passing through towns amongst crowded houses, but also in respect to plantations, corn-fields, stack-yards, and agricultural buildings in general adjacent to the line of the railroad; and they have ascertained with satisfaction that the ingenuity of scientific men has already been extensively, and to a great degree successfully, applied to the discovery of the most effectual means of meeting the danger. It does not appear, however, that as yet any plan has been devised which could be described as being at once completely effectual, and at the same time not injurious to the operations of the engine. The Committee are consequently not prepared to recommend the legislative enforcement of any specific plan for that purpose; but they are of opinion that if every Railway Company were made answerable for any damage that may be done by fire in consequence of the use of locomotiveengines, and if the parties who may be so injured were enabled to obtain due compensation by a short and unexpensive process, the interests of the Company would necessarily lead them to take every precaution in their power, and to avail themselves of any invention which might tend to increase that security from fire which the public are entitled to expect from all bodies of railroad proprietors who seek from Parliament the means of effecting their objects.

The Committee recommend that the Chairman should introduce a Bill for that purpose into Parliament.

EXTRACTS FROM EVIDENCE.

George Rennie, Esq., C.E., examined.

I know only of two accidents having ocfrom goods being fired. It was supposed the ashes tumbled out of the grate of the engine upon the railway, and that they were struck by the wheels, which struck the sparks into the waggons, and by those means they caught fire; but I never could learn whether that actually was the case. I am of opinion that protection from fire can be given by means of placing a hood or cylinder on the top of the funnel, and also by means of an efficient ash-box under the grate. I have brought a drawing which I will present to your Lordships. (Mr. Rennie explains the drawing.)

locomotive-engine.

"A locomotive-engine may be divided into three principal parts; viz. the furnace or boiler, which generates the steam; the slides and cylinders, which bring it into action; the cranks and wheels, which transfer that action to the whole machinery.

"The minor parts which maintain the connexion have no reference to the present question.

"The furnace is situated in the hinder part of the engine, as represented on the drawing, and surrounded on every side by water, except at the bottom, in which the fire-bars are placed. The fuel is put into the side of the furnace.

"The boiler is divided into three compartments, separated from each other by partitions of plate-iron; viz. the furnace compartment, situated at the hinder part of the engine; the tube compartment in the middle, containing the water; the hot-air compartment, which supports the chimney, and contains the cylinders, steam, and blastpipe. The upper part of the boiler, above the surface of the water, is appropriated to the steam-chamber and the steam-pipe. The fire-box is suspended to the bottom of the furnace with an interval or space between the upper edges for the admission of air to the furnace. The heat of the fuel should not exceed 1200 degrees Fahrenheit.

"The operation and power of the engine depend upon the magnitude of the furnace and number of tubes which produce the radient and communicative heat and consequent generation of steam.

..

In the working of the engine the air rushes through the furnace, where it becomes heated, thence through the tubes into the hot-air chamber, whence it is carried up the chimney by the draught. This draught and consequent combustion of the fuel depend upon the vacuum created in the air-chamber and chimney; and as it has been found by experience that the draught is greatly increased by allowing steam, after it has performed its office in the cylinders, to rush up the chimney, it is usual to have an eduction or blast-pipe communicating with the two cylinders, and from thence to the chimney, so that the steam rushes out by the alterna. tive operation of the pistons in the cylinders, thence into the chimney, where it creates a vacuum: the consequence has been a great augmentation to the power of the locomotiveengine.