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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    by admitting cold blasts through open windows, a proceeding, in the winter months, quite inconsistent with the architect’s main purpose—the conservation, at a healthy standard, of the actual warmth of the apartment. According to the best medical opinions, this standard should be 60° for children’s nurseries and sick chambers, and from 50° to 55° in rooms where persons are employed in sidentary occupations. Below this temperature, disease in the very young, and in the very old, is likely to be engendered. The supply of air, that most essential pabulum of life, has scarcely won due attention from architects; it is only permitted to enter houses clandestinely, and it comes in in jets and draughts. I have thought that such an important purpose, as the supply of this food of the breath, is deserving of an especial provision, and have, therefore, taken the liberty to suggest, that between each storey of every house, a space should be reserved for the exclusive reception of air, and which should freely communicate with the external atmosphere. Between this intersolar reservoir (measuring twelve inches in depth) and each subjacent apartment, a ceiling should interpose, in which a quadrangular opening two feet wide, and reaching from end to end, should be left; and a diaphragm, or sliding hatch, moving on rollers like a sash-frame of a greenhouse, should be fitted to close this on occasion. This sliding partition should consist of three panels, each two feet wide, and which should equal in measure the long diameter of the underlying room. One pa'nel should be imperforated, the second drilled with very small holes, and the third with apertures of a shade larger diameter. As this hatch is to move laterally on rollers, to such an extent, as to allow the quadrangular fissure to be entirely open on occasion, it will be in the power of the inmate below, by means of pulleys, to regulate the ventilation with the nicest regard to his feelings, He might shut out the air altogether, or graduate the quantity admitted to any degree, by sliding the hatch gradually over the air-way, or atmode proposed. A drawing in the lithographed sheet appended to this paper, displays the whole arrangement clearly. By this means, the impulse of the approaching air may be increased from a gentle wave-like motion to a brisk breeze, according to the desideratum of the moment; and the used air, ascending into the reservoir by the force of gravitation, would be carried off by the currents there prevailing. In nurseries, infirmaries, &c., it is desirable that ventilation should be controlled and nicely measured, and I believe the power of producing this result is obtained by the conjoint use of the mode of admitting air which I have named the atmode, and of the horizontal smoke-sewer or vomitorium. The means of accurate measurement is obtained by utihzing the evaporating property of air- currents. Evaporation and refrigeration are correlative, and the one is in fact an exact measurer of the other. Thus in Mr. Glaisher’s arrangement of the wet-and-dry-bulb-thermometer, the temperature indicates the quantity of moisture in the air; the lower the temperature of the wet bulb the less is the moisture; but the velocity of the air current increases evaporation, and augmented evaporation lowers temperature. By distinguishing the fall of temperature due to evaporation in the ordinary calm condition of the atmosphere, from the further effect due to air currents, we obtain a fine scale for noting degrees of air velocity. I take one of Glaisher’s double thermometers, and protect it in a glass cylinder from the action of draughts, and I find the difference between the wet and dry bulb to indicate the humidity or dryness of the quiet air. By its side I place another double thermometer, and on the second wet bulb I find marked the further effect of evaporation produced by the moving air. The difference between the two wet bulbs exactly indicates the force of the draught. The difference between the temperature of the dry bulb, and the dew point, being divided into a scale of 100° the exact expression, for the force of calm evaporation, of the augmented evaporation due to air currents, and of the difference between the two, may be in a moment ascertained by a reference to Mr. Glaisher’s tables, or by an easy calculation, (See lithograph drawing in the appendix).