An enquiry into certain principles of architectural physiology / by D.O. Edwards.

  • Edwards, David Owen, 1801-1878.
Date:
[1866]
Catalogue details

Licence: Public Domain Mark

Credit: An enquiry into certain principles of architectural physiology / by D.O. Edwards. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    sudden and capricious changes of the atmosphere, too, arising from the effect of heat and cold upon aqueous vapour, and generating the fluctuating aerial currents, called winds, must have soon suggested the expediency of adopting artificial heat, in addition to architectural covering, as a means of aiding the respiratory organs in their work, and in sustaining a wholesome range of temperature in the-dwelling house. This is a subject which has much occupied the attention of architects and engineers, and an extraordinary amount of ingenuity has been displayed in the various suggestions promulgated, with a view to make combustion perfect; to distribute its radiation widely, and to carry off the chymical products of ignition. There are many gentlemen present more skilled in the treatment of these matters than I am, I shall therefore confine my attention to a few points with which I am familiar. Notwith- standing all that has been said in favour of warming inclosed spaces, with hot water, steam pipes, air flues, close stoves, See., the open fire is still the favorite method in the popular mind. We continue to consume our fossil-fuel coal with an enormous waste of caloric and combustible matter. Large lumps, or ingots of coal, are placed in contact and sirbjected to ignition, the surfaces, which arc immediately exposed to the active fire, are decomposed and consumed, but the adjacent strata are heated at the same time, in different degrees; some to a degree not adequate to sustain combustion, but quite sufficient to expel the carboniferous gas which escapes up the chimney unconsumed. It has been calculated that by these losses, and the heat carried away in the smoke, a waste of 80 per cent, is experienced. To mitigate this great loss, and to ob^date other inconveniences. Dr. Arnott has endeavoured, with some success, to impart to the fire-grate some of the properties of the gas-retort, and to retain for use the carburetted hydrogen gas, and the solid particles of fuel, which are otherwise lost in the current of the smoke. With the same object I contrived my “ solid gas fire,” named “ the Atmopyre,” which I was permitted to exhibit to this Society sixteen years ago. On that occasion, I had the pleasure of showing an artificial cinder made incandescent by the combustion of hydrogen in air; a fact, indicating, as I then thought, and as I stiU think, the possibility of applying the hydro-oxygen fire to common use. The difficulty of economically separating hydrogen from oxygen in the decomposition of water postpones that triumph of art to the future; and our immediate care must be directed to the better management of our most comfortable, but very unscientific coal-fire. If Dr. Amott’s excellent idea of consuming smoke could be realized, there would still remain the need of carrying upwards the products of combustion, and the impediments which I experienced in applying my Atmopyre are still unsubdued in all chimneys of the usual character. In consequence of these impediments, my attention was early tinned to the means of ventilating ordinary chimneys, in such a way, as to command the occurrence of a constant upward draught. The ascent of the gases generated by combustion may be impeded by two different causes. First, in a still and humid state of the atmosphere, chimneys are filled with a body of air very nearly saturated with vapour, and, consequently, so conditioned as to resist the first feeble pressure of the rising smoke and its cognate gases. This hindrance can only exist during a perfect calm, and the first wave of air crossing the chimney-top dispels it. The most frequent and pertinacious obstacle to the easy escape of smoke, consists, secondly, in the disturbing effects of air-currents upon the chimney finials, which are generally terra cotta pots, or contorted zinc tubes. It is a law in pneumatics, the necessary consequence of the universal force of gravitation, that wide and strong cui’rents of air over-rule and attract to themselves all minor breezes. The impulse of wind is simply its local weight, but a degree of rarefaction is produced on the edge of every current, which causes an influx of the adjacent quiet air, and exerts beneficially an exhamient effect upon the draught of flues. Such a strong gust of wind approaching an ordinary stack of chimneys, of course, displaces, by its weight, the lighter atmosphere round about,