tinctly and easily comprehended. We remark further, that the suggestions of analogy between means and ends lie at the basis of invention. mind once felt and reverenced, and which glories in its shame; these are, no doubt, violent extremes, but they are still the extremes of a moral condition and a responsible agency, which is obviously the only ground of comparison between them. We shall find the explanation here given confirmed, if we examine the nature of rhetorical antithesis, which is nothing more than the utterance of the mental principle of contrast. Thus the whole life of man, from its beginning to its close, is expressed under the figures of the cradle and the grave, which mark its extremes. The variety in the circumstances and social condition of men, is included in a similar manner in the juxtaposition of their extremes; hence the common union of the terms poverty and riches, luxury and want, the palace and the cottage, the monarch and the beggar. On a similar comparison of abundance, and deficiency in some common quality, pride will suggest humility; learning, ignorance; health disease, and so on throughout all the contrasts that can be drawn between degrees of similar, not of different, qualities. If the end to be obtained be clearly understood, it will call up to the mind other ends already accomplished, together with the means by which they were effected, and these means will in turn suggest simpler and more effectual processes for accomplishing the purpose in view by the force of analogy or resemblance. În like manner, the perception of single events or facts will stimulate the mind to look for their causes, and to discover them by tracing out analogies in other effects. It was thus that Sir Isaac Newton discovered the universal law of gravitation from the fall of an apple, that the swinging of a lamp led Galileo to the discovery of the isochronic oscil4ations of the pendulum, and thence to the true system of the heavens. The same principle of analogy conducted Harvey, from the observation of valves opening from the heart in the arteries, and to it in the veins, to the demonstration of the circulation of the blood. This principle has, in short, been the pioneer of all great inventions and discoveries. It suggested to Columbus The practical uses to which this property of the mind the existence of a new continent. Its influence is very may be educated are manifold. It may be brought to remarkable in the discovery of printing; and, not to check our overweening exultation in our fortune or en accumulate examples, it was the generation of a little dowments by suggesting the condition to which we should vapour in a wine flask, barely sufficient to displace the be reduced by their removal. Like Philip of Macedon's cork, which suggested to Savery the practical employ-page, it may be brought to remind us, in the midst of ment of the mighty agency of steam to purposes which prosperity, that we are still men and exposed to the have given a new impulse to the human race if not changes of time. But, on the other hand, it may prevent us altogether altered its destinies. from sinking into blank and helpless despair, however hopeless our circumstances may appear, by presenting to us the reverse of the picture, and thus exciting hope and stimulating us to those efforts which are best calculated to retrieve our circumstances. Co-operating as it does with the laws already exemplified, especially with the power of discovering and seizing upon resemblances and analogies, it is calculated to lead to inventions in science and art. It may suggest the effects likely to issue from a given cause, were its leading properties either greatly augmented or much diminished. The fire which cheers and comforts us as it burns on the hearth, may suggest on the one hand the violence of a fierce conflagration, and on the other the slow combustion which goes forward in the lungs; and as we perceive that the fire on the hearth may be extinguished by excluding the air, or by saturating it with other vapours, we discover by analogy the means by which the most violent conflagration may be instantly quelled, as well as the no less important fact that impure exhalations will poison the air we breathe, and render it unfit to sustain the vital flame that burns feebly within us. Another law of thought is that usually denominated "association by contrast,' or that tendency which we all feel, on looking at any objects, or otherwise receiving an impression, immediately to think of its opposite. Passing by the strange account given of this principle by David Hume, we think it may be reduced to special resemblance. In what we call contrast it is manifest that there must be some common platform of resemblance between the most antithetical extremes, or else their comparison would have no meaning whatever. Thus, when we see a dwarf, the perception may call up the notion of a giant, but the idea of a giant is surely not the most contrary conceivable to that of the dwarf; a mountain, an ocean, or a period of time would be still more contrary, for they would not possess a single property in common with the dwarf, whereas the giant possesses all the properties of the dwarf, but in larger proportion; so also the life of the ephemeron, which is born and dies of old age in one day, may suggest the eternity of being; and the sight of a wretched criminal laden with the most heinous crimes, and led to execution amidst the execrations of his species, may bring before the mind the idea of his happy and innocent childhood, when he was an object of the tenderest care and love. Now these appear to be the very remotest contraries to each other, and yet, if we consider them more closely, we shall find that they all possess some common quality or qualities upon which the mind seizes as the ground of comparison. The breadth and extent which the high cultivation of the principle of contrast gives to the mind is astonishing. The power of observation and the range of suggestion are no longer confined to mere contiguity in time or place, nor to the resemblances and analogies of what is just before us; they expand themselves over the whole scale of conceivable being, from its lowest to its most exalted forms, with all intermediate degrees. Whilst at each degree the mind is aided by the other laws of association, which give it a command over all thoughts related in place or in time, as they were originally impressed upon it, and also of all their resemblances and analogics. In the case of the dwarf and the giant the common quality is size upon which the mind becomes intent: by reason of the extraordinary deviation of the dwarf from the common standard, associated with the general conception of man, this property of size becomes immediately the clue to other suggestions of proportion; the mind The fourth and last law of association is that of runs rapidly over the whole scale, and fixes upon the two abstract relations or the principle by which the mind extremes as including all intermediate degrees. One day abstracts from a number of objects some property or and eternity are alike duration, but they are the extremes quality common to them all, however different they may of brevity and continuance; and, as regards the maturity be in other respects. The common property thus abof criminal depravity, and the innocency of childhood, stracted for separate consideration may be either a casual they are opposite states or termini of moral being, between relation between the objects, but external to them, or a which vice and virtue may mingle in every proportion, relation between their inherent properties. The examfrom the first hesitating and fearful indulgence in a for-ples of the former are the following:-Position, as when bidden course, which disturbs the calm purity of childhood, to the hardened guilt which defies all laws, human and divine, retains scarcely a single trace of what the we observe a number of objects not with reference to their individual qualities, but to the place they occupy relative to one another. As in a village, for example, one house stands on a height, another in a hollow, and a third on the level; one is nearer, another farther off, and a third still more distant, and each bears a certain relation of position to all the others. Proportion, or the feeling we have of the relation which certain numbers and quantities bear to certain other numbers and quantities. Degree, as in sounds-when one is louder, shriller, or more continued than others, and similarly in all our sensations; and comprehensions, or the relations of parts to the whole. This is Dr. Brown's classification, and though it might be simplified so as to reduce several of the foregoing divisions to one more general, yet, as it offers a convenient arrangement of the different modes of relation, we have adopted it as it stands. The most important of the abstract relations is that between the inherent properties of objects independently of their external circumstances; and this depends upon the power which the mind possesses of discovering resemblances between them and of abstracting or withdrawing from all their other qualities those in which the similarity exists, and making them the object of its attention. Upon this mental power depends all classification, and consequently the existence of common names in languages. Without it everything in the universe would be to us simply an individual, with a proper name in which no other being would be indicated. The common names, or general terms, which express this conception of a general resemblance, enable us to indicate whole genera and species in a single word-as quadruped, horse, dog or animal, quadruped, biped; or taking the mere property of existence, being, animated, inanimate. It is this property of the mind which gives to language all its power of expression, and if we could fancy ourselves deprived of it no such thing as science would be possible, everything we knew and gave names to would exist apart from everything else in the memory. The feeling of these abstract relations is the source of all reasoning. We desire, for example, to know the exact relation of one object to another, but we have no means of considering them together; we select, therefore, a third object, which we know bears a certain proportion to the two former, and by comparing them both with it, we are enabled to arrive at a correct estimate of their proportion or other relation to each other. This third object is what is called the middle term in logic. The comparison of the first with it is the major premise; the comparison of the second with it is the minor premise. The estimate formed of the relation between the first and second by means of this comparison with the middle term is the conclusion; and the whole process, formally set forth, is called a syllogism. The capacity of the mind to grasp these abstract relations between things and ideas, so that they form permanent ties between them in the memory, combined with the principle of association by contiguity, constitute that special law to which we referred in the previous number, in accordance with which the series of propositions which make up a mathematical demonstration arise in the mind, in the order of their regular sequence or dependency. Many more observations suggest themselves upon this topic, but our space is almost exhausted, and we must bring our remarks to a close. The reader will have observed that we have in the foregoing pages dealt exclusively with the intellectual operations of the mind, and only adverted indirectly to the emotions. He must not infer from this that we look upon the feelings as beyond the influence of education; on the contrary, we believe that as the stimulating and exciting power of the whole mental constitution, and as the source of all our impulses to good or evil, the feelings require the most careful and delicate culture; that our moral susceptibilities and emotions are the affinities and repulsions which are intended by Infinite Wisdom to preserve us in right relations with Himself, as well as with all other beings and things, and therefore that to train them aright is of infinitely greater importance to human happiness than the most perfect intellectual discipline. We have been restrained from expatiating on this part of our subject, however, by two considerations; first, the necessity for compressing our remarks as much as possible; and secondly, the danger of touching upon any of those disputed questions which we promised at the beginning to avoid. There are several of our emotions, meanwhile, which may be safely discussed without venturing upon debatable land, but as these will necessarily be alluded to in our future remarks upon the practical art of education, we think it needless to dwell upon them in this place. DOMESTIC FIRES WITHOUT SMOKE. In the Journal of Gas Lighting for the past month, Mr. Julius Jeffreys communicates to its readers a plan for clearing the atmosphere of towns from the smoke of household fires. He proposes to make the bars of the fire grate hollow, and to connect these hollow bars with The grate is filled with gas coke, and a gas-pipe. the grate bars are perforated with small holes on that The gas side nearest to the coke they contain. being turned on by means of a stop-cock in the usual way, and lighted by a match, quickly ignites the coke in the fire place, which soon becomes glowing hot, and is kept so by the small jets of flame below and in front; and a bright and cheerful fire is kept up, burning with more or less intensity as the supply of gas is increased or diminished, and it burns without smoke. This is certainly an elegant and expeditious mode of kindling a fire, and Mr. Jeffreys shows it to be by no means a costly one. is evidently well suited for drawing-rooms and apartments where the furniture might be injured by smoky fires. It Mr. Davenport, one of the officers of the Society of Arts, has adopted a method somewhat similar to that proposed by Mr. Jeffreys, for the fires of bed-rooms, which are required to be lighted on short notice, and to burn without smoking. Mr. Davenport connects a hollow ring with the gas-pipes near the chimney, by means of a This hollow ring is flexible tube of the ordinary kind. entered between the two lower bars of the front grate, is perforated on the upper side with small holes, and the fireplace is filled with coke above the ring, which lies upon the bottom grate. The jets of gas issuing from the holes in the hollow ring being lighted ignite the coke above, and soon produce a clear and smokeless fire. The Transactions of the Society of Arts contain many valuable papers on the construction of domestic fire-places, and stoves for warming and ventilating apartments, which may be read and studied with advantage even now, although the use of coke, anthracite, and gas, has to some extent modified and superseded many of the ingenious contrivances there described. TRANSLATION FROM THE LAST REPORT FROM We announced in our last report that the consumption of iron material in England, particularly of the sorts required for railways and ship-building, had greatly increased. The same thing has also occurred in the last ten months in France, to such an extent, that by reason of the continual extension of railways, ship-building, and machine-making, the French furnaces, although remaining in work the whole year, have only partially been able to meet, from their own resources, the demands and requirements made on them. In consequence of this, the prices of French iron, which in the beginning of the year 1853 stood at: 12 francs the 100 kilos., or 2fi. 41 kzrs. the Vienna cwt., silver currency for coke-made pig iron, and 29fr. the 100 kilos., or 6fl. 294 kzrs. the Vienna cwt. silver currency for bar iron taken on the spot, have now risen to : 17fr. to 18fr. the 100 kilos., or 3fl. 481kzs. to 4fl. 2 kzrs. the Vienna cwt., for pig iron, and 34fr. to 35 the 100 kilos., or to 7fl. 37kzs. to 7fl. 50 2-5kzs. the Vienna cwt. for bar iron. Moreover, France imported in the year 1852: 664,633,000 kilos., 11,868,446 Vienna cwt. coal, 2,733,000 448,036 from England; coke, from the Zoll. districts d. STEEL (tempered and untempered) from the Zoll. districts e. SHEET IRON ... from the Zoll. districts f. TINNED IRON PLATES from the Zoll. districts WROUGHT IRON, such as an g. chors, chains, &c. ... MENT STRINGS from the Zoll. districts IRONWARE, lowest quality Influenced by these circumstances, and it being evident (Then follows the present French tariff.) a. 0 3 52 1 17 2 30 2 30 3 13 3 30 2 30 3 13 0 1 17 0 2144152 - ooooooo oo 201 1 0 58 6 26 52 0 12 53 3 52 15 0 19 19 from Zoll. districts It is therefore to be expected that, in consequence of the reduction of the import duty on steel, the exports of d. this article from Austria to France (which have been hitherto very small) will be largely developed, and, speculating on this, several purchases of steel have already been made in Stiermark for French account. IRON WARE:- IRON VESSELS, per ton bur then 4 30 5 59 0 32 12 25 4 0 ☎ 0 6 26 In addition to which each cwt. is chargeable 2'kreutzers for weighing-duties, besides " Siegeltaxe," and "Zettelgeld." MONEY.-60 kreutzers equal to 1 florin 10 florins silver £1 sterling. Present Exchange 114c. to 11 per pound sterling. Prices of Prussian Iron in Cologne under 19th Nov. as follows, viz. : Thalers. Coke Pig Iron 22 Vienna cwt. Silver Currency. We think we are not wrong in looking forward to this circumstance as a compensation for the reduced exportation of steel plates from Carinthia and Stiermark, which articles during a number of years have been exported in considerable quantity by way of Trieste, particularly to the southern states of America, for the manufacture of tools, and especially of those used for mining purposes. We therefore seize the present favourable opportunity to exhort all proprietors of Austrian steel works, in their own interest, to exert themselves earnestly, and to spare no German Charcoal Pig Iron, 24 per 1000lb. or 4fl. 10krs. sacrifice to get possession of this newly-opened market, and to maintain it by a uniform good quality of manu-Hoops, according to thick-149 facture, as well as by strict attention to instructions received. Unfortunately, in many steel-works, the late unfavourable state of things has induced an entire remodel-Angle Iron, 3-4 at 4 inches 43 ling of the establishments. Under these circumstances an association similar to those which have produced such good effects in other countries, is much to be recommended, in order that by such means, viz., through united efforts, an export trade in steel may be secured, not to France alone, but to other countries, into which, according to the last report of prices, it may be profitably introduced to meet their increased wants. FRENCH EXHIBITION OF 1855. The Commission of the Universal Exhibition assembled on Saturday at the Palais Royal, under the presidency o Prince Napoleon. His Imperial Highness, after reading the decrees instituting the Commission, pointed out the programme of its labours in the following terms:- "Gentlemen,-The Emperor confides to us a noble and honourable mission, in which France will show herself worthy of her name by the eagerness with which her artists and her manufacturers will respond to the appeal which is made to them. Our duty towards foreigners is We subjoin the new Iron Tariff, dating from the 1st of to receive thein with a liberal and friendly hospitality. January, 1854, giving at the same time the official ex- All opinions in matters of political economy are representchange for the month of January of fifteen per cent. dis-ed here, not to enter on fruitless discussions, which are count, when paid in paper money instead of silver; so that thus the import duty on 100 pound Vienna weight, paid in bank paper, may be exactly seen. foreign to our mission, but to co-operate with equal ardour, whatever may be our point of view, for the success of that work which is to illustrate France and Europe of vented by Mr. Loseby; for a detailed account of these, he nineteenth century. On this point, gentlemen, we must The Commission, and the two sections of which it is composed, then proceeded to the election of the vicepresidents. President Troplong was chosen vice-president of the General Commission, M. Baroche, vice-president of the section of the Fine Arts, and M. Billault vice-president of the section of Agriculture and Manufactures. Lord Cowley assured the Commission of the co-operation of England in this grand solemnity, of which she had furnished the first example, and congratulated himself on being called on to take part in the labours of the Commission. Home Correspondence. CHRONOMETERS. (a) With reference to Mr. Denison's letter, published in No. 58 of the Journal, I have only to observe, that a discussion continued in that style might possibly open up a new field of enterprise for briefless barristers, and advertise samples of their abilities, whilst it furnished some amusement to the members of the Society of Arts; but the substitution of personalities and other characteristics of bar advocacy, for dry facts and demonstration would not, probably, much advance either science or art. Yours, &c., COLONIAL POSTAGE. SIR,-May I inquire if the Association for the promotion of Cheap Postage is defunct. I have looked in vain in the recent numbers of the "Journal of the Society of Arts" for any notice of it. I hope it may not be so, and still more, that if it be unfortunately defunct, it may be recovered, in which case I would beg to offer it a hint. Their I always thought it rather complicated matters, and partially interfered with its successful working, by SIR, I shall be happy to discuss the papers that I may attempting anything beyond the regulation of that part have the honour to read before the Society with such of of the matter which exclusively belonged to the Home your correspondents, possessing sufficient practical know- Government. Most of the Colonies with legislatures ledge of the subject to guarantee the time being profit-have some time since had the management of their inland ably occupied, as may desire a candid and dispassionate postage. All that the Government at home should inquiry. As regards the different methods of secondary undertake would be to carry the letters from Great Britain compensation, it does not occur to me that any further to any part or parts of the different colonies; charging 1d. explanation is necessary, as the constructions themselves for the land carriage, and .d. for the sea transit; leaving are placed before the readers of the Journal. They to the legislatures to regulate all other charges. have now an opportunity of forming their own opinions representatives will understand and make known their on the merits of the different plans, and also of ascertain wants in their reports, and will be better able to carry ing the amount of error, which the different chronometers them out than the local governments or the central posthave exhibited in the trials at the Royal Observatory, by office in St. Martin's-lane. referring to a detailed account, published in No. 29 of the Journal, in which the errors are given as they occur in the government lists. Those interested in the subject may further consult parliamentary paper No. 1,006, Session 1853, from which the following extract, contained in a report of the Astronomer Royal to the Board of Admirality, is taken: "In regard to the merits of Mr. Loseby's invention, there are two distinct classes of trials; first, where the special experiment have been instituted for the examination of the success of the special construction in(a) This must close the present discussion on chronometers.-ED. In the home-coming letters all that the post-office should do would be in like manner to receive all at once in some point as most convenient, and be responsible for their delivery in this country, and for their forwarding to ulterior destinations as the case might be. The Society of Arts is much interested in the question. Its members are daily hindered in their correspondence on most interesting points owing to the charge, which amounts to a prohibition. I am, Sir, yours obediently, A MEMBER. (a) In the ordinary trial of this year, one of Loschy's chrono meters stood first. Datchett. CLOCKS. THE NEW GRAVITY ESCAPEMENT FOR and accordingly there have been multitudes of such escapements invented; but they have all failed in satisSIR,-You may remember that, at Mr. Shepherd's lec-fying some one or more of the conditions which are ture on electrical clocks about this time last year, I said, essential to their success, and consequently none of them that the invention of a remontoire, or gravity escapement, i.e. have ever come into use. What those conditions are will one which will give a constant impulse to the pendulum, appear from the following description of an escapement independent of all variations of force and friction, was no which satisfies them all. longer to be regarded as the great problem of clockmaking, for that several clocks with such an escapement were then going, one of them being the great clock for the Houses of Parliament, of which the pendulum has now been keeping time for above a year; though at the rate at which Sir C. Barry has allowed the clock-tower to advance since the clock was ordered in February, 1852, nobody of the present generation of men is likely to get much benefit from it, except, I suppose, the maker, who will of course have to be paid for it at the time fixed by his contract. Shortly afterwards I read a paper on that and some other recently invented escapements, which is printed in the "Cambridge Philosophical Transactions." But as publications of that kind have not a large circulation, andas I have now some further information to communicate respecting this invention, I avail myself of this Journal for the purpose; and, in order to make such further information intelligible, I must give some description of the escapement, and the objects of such escapements generally. Great as was the improvement effected in clocks by the invention of Granam's well-known dead escapement, it was only a mitigation, and not a removal of the disturbing causes of the commoner class of escapements, viz :-(1) the variations in the force of the train upon the escapement, owing to friction, the effect of cold on the oil, dirt, &c.; (2) the variations of friction on the pallets; and (3) the circular error, or the change of time due to the variation of the arc of the pendulum, which might arise from either or both of the above causes, independently of their own direct effects upon the rate of the clock. In an earlier paper in the Cambridge Philosophical Transactions, in 1848, I showed that the rate' of a dead escapement clock was expressed mathematically in three terms, corresponding to the above-mentioned three sources of error, and that the 1st and 3rd of those terms have a different sign from the 2nd; and moreover that they have no constant or definite relation to each other. And that is the reason why a clock of this kind is sometimes observed to gain while the arc of the pendulum decreases, and sometimes to lose, and vice versâ, according as the + or the terms happen to preponderate. And for this reason, also, if the rewere no others, the once popular cycloidal cheeks, and other equivalent contrivances for rendering pendulums isochronous in different arcs, are not only useless, but may sometimes aggravate the errors of a clock instead of diminishing them, however well they may appear to answer in violent experiments for increasing the arc of a pendulum by some great addition to the clock-weight, without regard to other causes, which in the natural state of things may produce equal or greater effects in the opposite direction. Another consequence of the nature of the errors of a dead escapement is, that in order to secure good timekeeping, everything must be done that can be done to diminish friction throughout the clock, such as jewelled pallets, very fine pivots, and high numbered wheels, all of which add considerably to the expense; and moreover, it is impossible to attach to it any striking or electricity discharging work without the risk of disturbing the_rate by the additional friction which all such appendages involve. It was long ago perceived that all these evils might be avoided if an escapement could be made to give a constant impulse to the pendulum, and having no contact with it accompanied by any sensible amount of friction; Some extra copies of it were printed for Mr. Weale, the publisher of the "Rudimentary Treatise on Clocks," and may still be had from him. |