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his house are extremely brilliant; and the variety and neatness of their application worthy of praise.

He deserves credit too, we think, for calling the public attention, more than had been done before, to the peculiar advantage of coke as a cheap and agreeable fuel. This sub stance is the residuum that is found after all the evaporable matter has been expelled from the coal by heat. It comes out from the distilling process in large spungy masses, greatly diminished in weight, but increased in bulk nearly one third. Though somewhat more difficult of ignition than coal, it burns longer, and gives out a steadier and more intense heat.

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That it should do so, will not appear strange to our chemical readers, (and who is there now, that does not know something of chemistry?), when it is considered that the quantity of matter, which, in the combustion of coal, is changed from a solid to a state of elastic fluidity, must necessarily carry off much caloric in a latent state; while the glow of the coke radiates with an intensity unimpaired by any demand of this kind. The same respectable chemist we formerly mentioned, bears testimony to the superiority of coke. 'I have learned,' says Mr Accum,* that the heat produced by coke, when compared with that which can be obtained from coal, is at least as 3 to 2.' Thus he found, that it required three bushels of coal to distil a given quantity of water, and only two of coke. He tried the two substances also by combustion, with a certain measure of oxygen gas, by the fusion and the reduction of metals, &c.; and the same result was obtained, a result certainly not unimportant, since it proves that, by being forced to yield the material of a beautiful light, coal is actually improved very considerably in its power of giving heat. We have not the least doubt that this coke, as Winsor produces it, and as we have seen it used in his house, might be introduced to form, if not the whole, at least four fifths of our common fires, with a very great addition of comfort, cleanliness and economy. Let it be observed, however, that we possess no facts that warrant us in pushing this conclusion any further than regards the coke of Newcastle coal. Mr Murdoch, though he makes proper allowance for the coke produced in his process, does not enlarge at all on its qualities; and it is probable, that some species of coal generate coke too dull and difficult of ignition for consumption in our grates, and only fit to be used in stoves and furnaces where there is a strong draught. But we are persuaded, that the greater proportion of the other varieties in the island will be found, on trial, to yield the same sort of coke as Winsor's, and that it can never be produced in such quantity, by the extended use of

* Appendix to Report of the Committee, &c.

the

the gas lights hereafter, that the demand will not fully and rapidly absorb it. Its merits have long been acknowledged in many processes of art; and it is prepared from coal with the loss of all the volatile ingredients in the great manufacturing districts; and if the price were lowered, by turning the gas to account, it could hardly fail to become a favourite fuel.

We have taken no notice of the tar and alkaline liquor which are copiously produced in the distillation; because we have few facts to go upon in estimating their value. The former is useful as a coating to preserve, from the worm and rot, timber exposed to the air, or lying under water; and it is not unlikely, that other more important uses may be found for it. As to the liquor, we believe it to be of no use whatever; and it is one of the absurdities of Winsor's calculations, to reckon at one shilling per gallon, a substance, of which, we are convinced, no man in London would purchase a hogshead at the expense of ware, house-room.

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When we said that the facts of Mr Winsor and his friends are less satisfactory than the others we recorded, we alluded to the circumstance, that, while he makes us stare at the unparalleled extravagance of his tables, where he gravely strikes a balance of annual profit to the nation at large, of one hundred and fifteen millions, and while, by a singular effort of moderation, he reduces the gains of his subscribers to the absolute certainty' of only 6007. a year for every 5. adventure,'-he cautiously avoids detailing minutely the expense of the apparatus, or taking, as an item on the debtor side, the interest of capital sunk, which, in Murdoch's statement, exceeds the annual expense, in the ratio of 11 to 1. We need not add, how much this must falsify all his conclusions, even if he had not disproved them himself by a deductio ad absurdum. The committee-composed, as their Report shows, of sensible, but not scientific men-do away half the value of their experiments, when, in a Memorial addressed to the King, they candidly subjoin to their account of them- Their present experience does not enable your Majesty's memorialists to calculate the expenses of the process, of management, of tubes, and pipes, &c. with any tolerable degree of precision. p. 19. The experiment in Pall Mall, therefore, proves as yet nothing more, than the possibility of lighting up a street with gas ;—a curious fact, without doubt; but we cannot call it a very important one, till we be enabled to add, that this can be done at a cheaper rate than with oil. It is not unlikely that it may; and we strenuously advise the committee, while they have the command of money, instead of basking in the sunshine of delusive hopes, to institute another trial, in which all these expenses shall be rigidly

noted,

noted, and faithfully carried to account. It is a point which it is desirable to ascertain, though we by no means agree in the common opinion, that on its decision depends the question of the economical advantages of the gas-lights. The committee were unfortunate in choosing this for their experimentum crucis. The lights required in streets are at considerable intervals, and, consequently, the range of tubes is extensive and costly; and, going to a great distance from the centre of supply, must be subject to accident and derangement. In lighting the streets, too, the gas must beat out of the market the coarsest and cheapest of all materials; so that we can imagine a failure, in this instance, not inconsistent with its producing great national and individual benefit.

There is one circumstance, in which, as far as we can judge from our imperfect knowledge of Winsor's process, it is superior to Murdoch's. The latter seems to follow the usual mode of distillation, by putting the vessel that contains the coal into the centre of a furnace. But Winsor puts the fire in the centre, and (leaving only space sufficient for a draught of air) surrounds it with the coal that is to be carbonized; the evident advantage of which is this, that the least possible heat is wasted, as, in flying off, it encounters the coal on every side. Accordingly, we find, that, in Murdoch's statement, a sixth part of the annual expense goes for the purchase of common coal to distil the cannel which he employed; while Winsor's carbonizing process is performed by the refuse cinder of a former operation; and as this cinder does not appear in the estimate of coke produced, it may in fact be considered as costing nothing. Before taking leave of Mr Winsor, we shall present the reader with the results of his analysis of coal, which, from the specimen he has given us of his powers of exaggeration, we should have been cautious of admitting among authentic facts, had not the Committee declared, that the experiments were repeated in their presence, and that they corroborated Winsor's printed statement in the most satisfactory manner. Two pecks of Newcastle coal, weighing 36 lib... produced three pecks of coke, weighing 24 lib. 2 oz., about 34 lib. of oily tar, and about 4 of alkaline liquor; and, as the only other product was gas, it is concluded that gas constituted the remainder of the weight, amounting nearly to four pounds.

From the foregoing facts and reasonings, we think ourselves enitled to draw the following conclusions.

I. In all manufactories, whether on a large, middling, or small scale,-in all public offices, printing-houses, theatres, lighthouses, &c.-in short, wherever much light is required in a given space, the gas-lights may be introduced with very great advantage. We

need

need not remind the reader, how large a proportion of the artificial light used in this manufacturing country is comprehended in this description. It may be objected to the universality of our conclusion, that the price of coals differing very much in different places, will occasion a variation in the expense of procuring gas. But there are two reasons why this should have less effect than at first sight might be imagined. In the first place, we find, upon examining Mr Murdoch's statement, that of 6001, the estimated yearly expense of lighting the cotton mill, 550%. consist of interest of capital, and tear and wear of apparatus, leaving the cost of coal only 50%. ;-a sum so trifling, when we reflect that it replaces 20007, worth of candles, that the price of coal, even where it is highest, can but slightly affect the general profits. Secondly, the coal, by yielding the gas and other volatile products, is converted into a substance, increased in bulk, and in the power of producing heat; and as a manufactory generally requires heating as well as lighting, there will be a gain both ways. By distilling his coal, instead of burning it as it comes from the pit, the manufacturer will save his candles, and improve his fuel. One effort at the outset, in erecting a proper apparatus, will reduce his annual disbursement, for these two articles of prime necessity, much in the same manner (though in a far greater degree) as the farmer gains by building a thrashing machine, and laying aside the use of the flail.

II. When we reflect on the small number of trials that has yet been made, and the expensiveness and awkwardness of first attempts, we may reasonably expect considerable improvements as the practice becomes more general, so as to turn the scale still more decidedly in favour of the gas-lights. Anxious as we are to avoid the charge of visionary speculation, we cannot help anticipating the pretty extensive introduction of them into private houses. Mr Lee has set the example:-the whole of his house at Manchester, from the kitchen to the drawing-room, is lighted solely by gas. Its properties render it particularly fit for ornamental illumination. As there is nothing to spill, the flame may be directed either downwards, upwards, or horizontally; and the points from which it issues may be disposed in any form that taste or fancy may suggest. We are perfectly aware of the difficulties that oppose such an application of the gas; but we have unbounded confidence in the skill and ingenuity of our countrymen, when they are once fairly brought into action. The gigantic

steam-engine has been reduced to a convenient, and even portable size; and its power made so divisible, as to be dealt cut in portions to petty inanufacturers, who know nothing of the machine, but by the power which they hire. It has been proved,

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we think, that, in the case before us, there are materials to work upon; and, whenever this becomes the general opinion, we shall not be afraid of the best means being adopted to turn them to account. Whether ingenuity should be left to its own workings, and the stimulus of private gain, or restrained and directed by the interference of Government, is a question which we do not feel ourselves called upon to decide.

ART. XIII. An Examination of the Causes which led to the late Expedition against Copenhagen. By an Observer. Hatchard.

1808.

TH HE privilege which we enjoy in this country, of discussing every public occurrence with all the freedom and the keenness which belong to our political or physical constitution, though productive of incalculable benefit on the whole, has been the source of some evils. The most considerable perhaps of these, is the habit to which it has formed us of limiting our attention to the subject of the day, and dismissing entirely from our reflection every topic upon which our contending parties have once fairly delivered their opinions. Among a nation of newsmongers and politicians, this can scarcely be otherwise. Novelty is the great demand of the superficial; and, where every day supplies something new and disputable, the most important measures must take their turn with the most insignificant; and discussions, which are to influence the fate of future generations, must give place to the paltry recriminations of individuals whose names are notorious.

There are topics, however, which it seems to be a duty to try at least to rescue from this periodical oblivion, and to which the public attention ought if possible to be directed, after they have ceased to be the watchwords of faction, or the vehicles of personal abuse. There are objects now and then to be seen above the political horizon, which, though confounded, by the dazzled and shortsighted eyes of party or of idle curiosity, with the transient meteors of the atmosphere, are yet destined to hold their course in the eyes of many generations, and to exert a visible influence on every part of the system in which they appear. There are events of great example, and of terrible warning. There are measures which leave a taint or a healing virtue behind them, long after the period of their individual consummation; and principles which, though first disclosed in events that seem but comnon subjects of wrangling or censure, yet entail a blessing or a

curse

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