A practical treatise upon warming buildings by hot water : and upon heat and heating appliances in general, with an enquiry respecting ventilation, the cause and action of draughts in chimneys or flues, and the laws relating to combustion / rewritten by Frederick Dye.

  • Charles Hood
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: A practical treatise upon warming buildings by hot water : and upon heat and heating appliances in general, with an enquiry respecting ventilation, the cause and action of draughts in chimneys or flues, and the laws relating to combustion / rewritten by Frederick Dye. Source: Wellcome Collection.

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    at i8o°, but by this means we are able to get better results under certain conditions. In indirect work, which affords the required heat wholly by imparting warmth to new air passing into the building, the humidity of the air is less affected and no noticeable dryness to the atmosphere can be detected. It is, however, in stove work, and heating air by stoves, that this property of heat diffusion in metal gives the most marked beneficial results. When treating open fire-grates we shall speak of the disadvantages experienced by the good conductive power of iron, and the various means of obviating the difficulty. Radiation of Heat. To clearly grasp the existing theory of radiant heat (radio, to emit beams or rays) we have to understand that there exists around us, in every conceivable space, an infinitely thin and subtile medium, which is termed the ether (or the interstellar medium). It is quite independent of the atmo- spheric air, or, we may say, is mixed with it, and this medium is the means by which radiated heat, as also light, is trans- ferred or conveyed from a hot body to surrounding objects. Radiant heat is therefore the motion of heat transmitted to the ether, which motion is carried or propagated in the form of waves in straight luies from the source of heat. It is not at all necessary that air be present to effect the phenomena of radiation, for if we suspend a thermometer in a vacuum and apply heat outside, or place a heated substance in the vacuum and the thermometer outside, or place both in a vacuum, we find that the transmission of radiant heat is still manifested. Consequently we must believe that this ethereal medium is of a totally different character to air or gases, as it cannot, apparently, be withdrawn from a vessel in the manner we should exhaust it of air. We have already mentioned that the fact of a material conducting heat satisfactorily, as iron does, is not sufficient to ensure success to a hot-water apparatus, for the simple reason
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