I consider the system of open fires of coal or wood to be by far the most healthy of all the systems which have now been described; and, with due Attention to the methods by which the consumption of fuel can be diminished, while greater efficiency in the use of the fuel is obtained, I do not see that it can well be improved upon for private houses in the British Isles. It is however, desirable that a special supply of air should be brought to the fire from outside wherever possible.

Where it is desired to use some auxiliary system, then I consider that low-pressure hot-water is, taking it all round, the most suitable for general use, as being perfectly safe and requiring little attention. I do not consider systems of heating by heated air desirable, if they arc to be used instead of fires, but as auxiliary means of providing general warmth, they may be of service; the chief objection in my mind to the use of heated air is, that it is necessary to breathe the heating medium, whereas the ideal to be aimed at is to heat the objects, the walls, and the persons in the rooms, while leaving the air comparatively cool for breathing. Systems of steam heating and high-pressure hot-water heating have their uses as auxiliary means of heating, and are specially to be recommended where it is desirable to occupy as little space as possible with the pipes.

Close stoves and close fireplaces are, in my opinion, not to be recommended in preference to open fires, except upon the basis of lower financial cost of maintenance. The cold of the British winter is not usually so severe as to call for such means of heating, and although perfect smokelessness can be obtained the use of some of these apparatus, yet the smoke can so far be diminished the use of suitable open grates that they cease to be very objectionable in this respect.

Gas-fires are not, in the author's opinion, desirable, as there is usually a smell produced by them; if the register is not very carefully adjusted, either meet of the heat disappears up the chimney, or, on the other hand, invisible products of combustion, in the form of carbonic acid gas, etc, are discharged into the apartment.

In closing, I would say again that it is deniable to warm the whole of the house and not a mere part of it, and to prevent draughts by arranging for special inlets and special outlets of the air, and this can Be done perfectly in the case of new buildings, although probably with only partial success in the case of buildings already completed.