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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[June, 



nigbt a spike be expected to last, where even a bolt head is quickly 

 buroed away ? We might proceed to show, that the spiking of flues 

 ■jvould not merely render repairs more frequent, but also more difficult 

 that it would be inconvenient to clean, and in some measure danger- 

 ous to meddle with flues studded with these Caledonian stiletlos, fresh 

 from the armoury of Dircks and Co. — the unfortunate sweep or boiler- 

 mender being reduced to much the same condition as Regulus in his 

 barrel of nails, or as a heretic on the eve of being impaled upon the 

 pious spike surfaces of the martyrology. We might also show that 

 the salt which collects in the flues of marine boilers wherever there is 

 a leak could only be detached from the spikes with great difficulty, 

 some of the spikes, too, being probably broken in the attempt. But 

 we feel that it would be a useless multiplication of words to enter 

 upon such topics ; we have drawn the veil sufficiently aside to show 

 the fallacy and folly of this project, and we leave those parts of it 

 which it would be superfluous to expose, to the judgment or com- 

 passion of our readers. 



We had almost forgot to mention that the application of spikes to 

 boilers is not a new idea. Spike boilers were in use many years ago 

 in the United States — that hot-bed of preposterous subjects — and we 

 are told that a spike boiler is described and figured in Gordon's book 

 on locomotion. Such boilers of course did not answer. Mr. Beale of 

 Greenwich attempted to rationalize the scheme ten years ago, by 

 making the spikes hollow and filling them with water. But even with 

 this modification, the project was found unproductive of benefit, and 

 Lighly objectionable in many respects. After much labour and capital 

 had been uselessly expended, it was in consequence abandoned. 



Let us now proceed to render indelible our former remarks upon 

 the illusory nature of the smoke-preventive project. The pretensions 

 of this scheme to a superiority over all pre-existing schemes rest 

 chiefly upon the allegation, that it is not smoke which is attempted to 

 be consumed, but gas. We admitted, it will be remembered, the 

 superiority of the smoke-preventive principle over that which has for 

 its object the combustion of smoke, and we expressed our readiness 

 to give this gentleman whatever credit might appear due to him, 

 either for having been the first to propound that principle, or the first 

 to practically apply it. But we denied that the principle of smoke- 

 prevention was even attempted to be carried out in this gentleman's 

 furnace — that his furnace could not therefore possess any superiority 

 upon that score ; and we showed that smoke-prevention had, pre- 

 viously to Mr. Williams' expositions, been advocated in an essay 

 attributed to Mr. Bourne. These statements, if substantiated, will 

 certainly reduce Mr. Williams' merits to a superficies differing from 

 nonentity by a quantity incalculably small. Let us examine what is 

 urged in opposition to them. 



The difterence between smoke and gas, it will be recollected, we 

 stated was, that the one was the product of imperfect combustion, 

 and the other was not the product of combustion at all, but of distil- 

 lation merely ; and we said that for this gentleman's furnace to be a 

 smoke-preventive furnace it was indispensable that no combustion 

 should be carried on in it — a condition we showed to be incompatible 

 with any conceivable mode of working a furnace so constructed. We 

 argued then that combustion must be carried on in this gentleman's 

 furnace, if it were in action at all ; and that it would be a mere delu- 

 sion to pretend that because there were doors to the ash pit the fire 

 could therefore be kept alive without a supply of air. To this Mr. 

 Williams replies, that he is guilty of no such absurdity as that of 

 excluding the air from the ash pit altogether; and that the doors he 

 places upon his ash pit are merely for the purpose of regulating its 

 admission. In other words, it would appear that the use of these 

 mysterious doors is merely to regulate the draught — a purpose which 

 a single damper in the chimney would accomplish. It would further 

 appear to be admitted that air is allowed to enter the furnace, and 

 that combustion is carried on therein; so that it is smoke, not gas, 

 ■which this gentleman attempts to consume, and his furnace is, there- 

 fore, virtually admitted to be a mere smoke-burning furnace, as we 

 proved it to be in our former analysis. 



In our previous observations we remarked that one of the most 

 serious objections to all smoke-burning plans was the necessity of 

 admitting an excess of air into some part of the flue or furnace,' the 

 refrigeratory eftect of which materially detracted from the calorific 

 efficacy of the combustible parts of the" smoke. Mr. Williams informs 

 us, that in his plan an excess of air is unnecessary, fccoi.se the air is 

 thoroughly diffused; and he is kind enough to hint at the "chemical 

 error" we are supposed to have committed in supposing an excess of 

 air to be indispensable, inasmuch as an excess of air, he says, is rather 

 a serious impediment than a necessary aid to combustion! We feel 

 that an apology is due to our readers for entering upon the demon- 

 stration of truths with which every schoolboy is familiar; but we have 

 no alternative between leaving this gentleman unconverted and de- 



scending to expositions which every one of common capacity will 

 esteem as trite, obvious, and insignificant. 



The necessity for the admission of an excess of air, tlien, to accom- 

 ])lish the combustion of the imflammable matters existent in smoke, 

 does not arise from an unequal diff'usion of the air among the smoke, 

 but from the co-existence of a large quantity of uninflammable gas, 

 the product of combustion, which is commingled with the matters 

 sought to be burned. To descend to the phraseology of Mr. Williams, 

 the uninflammable gas operates unfavourably upon the combustion of 

 the inflammable gas meckanicallij by the interposition of its atoms, 

 and chmically by the absorption of heat. The latter of these evils 

 might be obviated by raising the uninflammable gas to a high tempera- 

 ture, but the former is insuperable so long as the quantity of oxygen 

 is unvaried, and is greater in amount in proportion as the quantity of 

 uninflammable gas is large. To take an extreme case ; suppose that 

 in every cubic inch of smoke there were only an atom of combustible 

 matter present — the rest being all incombustible gas arising from 

 combustion — and suppose that to every cubic inch of smoke two atoms 

 of oxygen were admitted ; what chance would there be that these two 

 atoms of oxygen would come into sufficient proximity to the combus- 

 tible atom to fulfil the conditions indispensable to combination '. It is 

 idle to talk of diffusion as a remedy for this evil ; the difficulty is not 

 that the gases are insufficiently mixed — for we have supposed the 

 mixture to be homogeneous — but that the atoms are too far apart, and 

 that an incombustible substance is interposed, which separates the 

 atoms to be combined as effectually as if there were a wall or partition 

 between them. This difficulty is only to be mitigated either by in- 

 creasing the proportion of the combining substances, so as to render 

 the quantity of the incombustible gas relatively less, or by so increasing 

 the quantity of the supporter of combustion as to afford some reason- 

 able prospect that the combustible atoms, when equably diftused, will be 

 sufficiently near some of the atoms of the supporter to be within the 

 range of combining attraction. The latter expedient is the only one ■ 

 available in practice, and this expedient is in effect neither more nor 

 less than the admission of an excess of air into the flue or furnace, the 

 word "excess" meaning a greater quantity than is proper to atomic 

 saturation. In all smoke-burning furnaces, then, it is necessary to 

 admit an excess of air into some part of the flue or furnace, to accom- 

 plish the combustion of the inflammable parts of the smoke; and this 

 excess of air, by its cooling agency, diminishes the available quantity 

 of heat the combustible parts of the smoke would otherwise surrender. 

 Any diffusion appliance, whatever be its merit, leaves this difficulty 

 untouched ; and this, the chief obstacle to the success of all smoke- 

 burning projects, attaches as much to this gentleman's furnace as to 

 any other. 



But further ; Mr. Williams observes " I am told the sole peculiarity 

 of my plan is that the air enters by a greater number of holes than 

 usual. Will the reviewer inform your readers whether this peculiarity 

 be not the very one which characterizes the Argand burner? Again, 

 whether of two smoke-burning projects the least objectionable is that 

 which admits the air at one hole or at many holes, it would be irrele- 

 vant to inquire. Now, Sir, that is the real point worth inquiring 

 into, and this blinking tlie main question at issue will not go down with 

 your scientific readers." If our scientific readers do not do more than 

 blink at this exposition, the fault certainly does not lie with Mr. 

 Williams. We thought the question had been whether this gentle- 

 man's furnace were a smoke-burning or a smoke-preventing furnace; 

 but it would appear that the claim to the title of a smoke-preventing 

 furnace is relinquished, and the real point now to be determined is 

 whether this smoke-burning furnace is better or worse than other 

 smoke-burning furnaces. This is at least intelligible ; yet in the face 

 of this announcement, and in the very same paragraph, we are told 

 that this furnace is no more asmoke-burning furnace than the Argand 

 burner is a smoke-burning lamp. The Argand lamp and the Argand 

 furnace, we are told, very closely resemble one other — and in what 

 respect? there are small holes in both. 



In our former remarks, we stated that it was smoke, not gas, that 

 was generated in this gentleman's furnace ; and that whether the air 

 were admitted by one hole or by a thousand holes, the nature of the 

 tiling to which it was admitted could not be altered thereby. But 

 because an Argand burner consists of a tube perforated with small 

 holes, and is a smoke-preventing arrangement, this gentleman's diffu- 

 sion apparatus, being also composed of tubes perforated with small 

 holes, is said to be a smoke-preventive arrangement likewise. The 

 substance to which air is supplied through one hole, though smoke, is 

 no sooner supplied with air through many holes than it immediately is 

 turned into gas ; so that we have only to apply this very reasonable 

 doctrine to prove that the infusion which, when made in an ordinary 

 vessel, we are wont to distinguish by the term coffee, will inevitably 

 be transformed into chocolate, or something still more wonderful, if 



