Twentieth Century Inventions: A Forecast

by George Sutherland

At the same time the risk of spreading "smuts" over the room can be entirely avoided first by keeping the whole length of pipe perfectly air-tight, and attaching it in such a way as to be readily removed for inspection; and, secondly, by placing the outward vent in such a position that the gentle current must mount upwards, and any dust must fall back again into a wide funnel-shaped orifice, and by covering the latter with fine wire gauze. An apparatus of this kind acts as a remover of dust from the room instead of adding any to it. One necessity, however, is the provision of motive power, very small though it be, to work the fan or otherwise promote a draught.

Electric heating is, however, the method which will probably take precedence over others in all those cases where systems are tried on their actual merits apart from sentiment or usage. The wonderful facility afforded by the electric heating wire for the distribution of a moderate degree of warmth, in exactly the proportions in which it may be needed, gives the electric method an enormous advantage over its rivals. The fundamental principle upon which heating by electricity is generally arranged depends upon the fact that a thin wire offers more electrical resistance to the passage of a current than a thick one, and therefore becomes heated. In the case of the incandescent lamp, in which the carbon filament requires to be raised to a white heat and must be free to emit its light without interference from opaque matter, it is necessary to protect the resisting and glowing material by nearly exhausting the air from the hermetically sealed globe or bulb in which it is enclosed.

But in electrical house-warming, for which a white heat is not required and in which the necessary protection from the air can be secured by embedding the conveying medium in opaque solid material, the problem becomes much simpler, because strong metallic wires can be used, and they may be enclosed in any kind of cement which does not corrode them and which distributes the heat while refusing to conduct the electric current. A network of wire, crossing and recrossing but always carrying the same current, may be embedded in plaster and a gentle heat may be imparted to the whole mass through the resistance of the wires to the electricity and their contact with the non-conducting material.

Concurrently with this method of heating there is gradually being introduced a practice of using metallic lathing for the plastering of dwelling-rooms in place of the old wooden battens generally employed for lath-and-plaster work. The solution of the practical problem which has to be faced seems to depend upon the prospect of effecting a compromise between the two systems, introducing thin resisting wire as the metallic element in such work, but making all other components from non-conducting material. In the event of any "cut-out" or "short-circuiting" occurring through accidental injury to the wall, it would be very inconvenient to be compelled to knock away the plaster. Moreover, it is not necessary for ordinary warming purposes that the whole of the wall, up to the ceiling, should be heated.

Accordingly the system which is likely to commend itself is that of constructing panels on some such principle as the one already described, and affixing them to the wall, forming a kind of solid dado from three to four feet from the floor. These can be fastened so as to facilitate removal for examination and repairs. When the current is switched on they are slowly warmed up by the heat generated through the resistance of the wires, and the air in the room is gently heated without being vitiated or deprived of its oxygen as it is by the presence of flames, whether of fuel or of gas. Warming footstools will also be provided, and a room heated in this way will be found eminently comfortable to live in.

This method of house-warming having once obtained a decided lead within the cities and other localities where a cheap electric current is available, somewhat similar systems, adapted for the heating of walls by hot air in tubes, instead of by resistant wires, will be largely adopted in the rural districts, more particularly in churches and other places of public assemblage. The progress made in this direction during the last few years of the nineteenth century is already noteworthy, but when electric-heating really gets a good chance to force the pace of improvement, the day will soon arrive when it will be regarded as nothing less than barbarous to ask people to sit during the winter months in places not evenly warmed all through by methods which result in the distribution of the heat exactly as it is wanted.

Ventilation is another household reform which will be very greatly accelerated by the presence of electric power of low cost. The great majority of civilised people, as yet, have no idea of ventilation excepting that highly unreasonable kind which depends upon leaving their houses and other buildings partly open to the outside weather. One man is sitting in church under a down draught from an open window above him, while others, in different parts of the same building, may be weltering in the heat and feeling stifled through the vitiated air. In dwelling-houses the great majority of living rooms really have no other effective form of ventilation than the draught from the fireplace. The strength of this draught, again, is regulated to a very large extent by the speed and direction of the outside wind.

In calm and sultry weather, when ventilation is most needed, the current of air from the fireplace may be very slight indeed; while in the wild and boisterous days succeeding a sudden change of weather, the living rooms are subjected to such a drop in temperature and are swept by such draughts of cold air that the inmates are very liable to catch colds and influenza. Hence has arisen in the British Islands, and in the colder countries of Europe and America, the very general desire among the poorer classes to suppress all ventilation. Rooms are closed at the commencement of winter and practically remain so until the summer season. Many people whose circumstances have improved, and who pass suddenly from ill-ventilated houses to those which have better access to the outside air, find the change so severe upon their constitutions and habits that they give a bad name to everything in the shape of ventilation. Meanwhile the dread of draughts causes people to exclude the fresh air to such an extent that consumption and many other diseases are fostered and engendered.

All this arises mainly from the very serious mistake of imagining that it is possible to move air without the exercise of force. In the case of the draught caused by a fire no doubt an active force is employed in the energy of the heated air ascending the chimney, and in the corresponding inrush. This latter is usually drawn from below the door—the very worst place from which it can be taken, seeing that in the experience of most people it is by getting the feet chilled, through draughts along the floor, that the worst colds are generally contracted. Fireplaces are not unusually regarded as a direct means for ventilation, and with regard to nearly all the devices commonly adopted in houses and public buildings, it may be said that they lack the first requisite for a scientific system of renewing the air, namely a source of power by means of which to shift it from outside to inside, and vice versâ. There is no direction in which a more pressing need exists for the distribution of power in small quantities than in regard to the ventilation of private and public edifices.

The circular fan, placed in the centre piece of the ceiling and controlled by an electric switch on the wall, is the principal type of apparatus applicable to the purposes of ventilation. As electric lighting of dwelling-houses becomes more common, and ultimately almost universal within cities, the practice will be to arrange for lighting and for ventilation at the same time. But, unfortunately, the current now principally employed for electric lighting and consisting of a series of impulses, first in one direction and then in the opposite, "alternating" with wonderful rapidity, is not well adapted for driving small motors of the types now in use. One improvement in domestic economy greatly needed in the twentieth century consists in the invention of a really effective simple and economical "alternate-current" motor. This is a matter which will be referred to in dealing with electrical machines. That the problem will be solved before many years have passed there is no good reason to doubt.