is concerned the rule should be that
those handling infected materials have a special uniform[22] which is
cleaned and disinfected after the day's work is done. The hands should
receive careful attention, as otherwise the disinfector may carry
infection to his home. The best method of disinfecting the hands is to
thoroughly wash and scrub them for five minutes with green soap,
brush, and water, then immerse first for one minute in alcohol, and
then in a hot 1:1,000 bichloride solution. The nails should be
carefully scrubbed and cleaned.

FOOTNOTES:

[20] Blankets, carpets, and rugs should be frequently hung out on the
line in the bright sunlight.--EDITOR.

[21] Unless books are valuable it is best to burn them. Paper will
hold germs for several weeks. Recent experiments show that certain
pathogenic bacteria, including the bacilli of diphtheria, will live
for twenty-eight days on paper money.--EDITOR.

[22] Duck, linen, or any washable material will do.--EDITOR.

CHAPTER XI

=Cost of Conveyed Heating Systems=[23]

In our variable climate, with its sudden and extreme changes in
temperature, the matter of heating and ventilation demands the serious
attention of all houseowners and housebuilders.

The most common method of heating the modern dwelling is by a hot-air
furnace in the cellar, with sheet-metal ducts for conveying the heated
air to the various rooms. The advantages of a furnace are cheapness of
installation and, in moderate weather, a plentiful supply of warm but
very dry air. The disadvantages are the cost of fuel consumed, the
liability of the furnace to give off gas under certain conditions, and
the inability to heat certain rooms with some combinations of
temperature and wind. The cost of installing a furnace and its proper
ducts in a ten-room house is from $250 to $350; such a furnace will
consume fifteen to twenty tons of anthracite coal in a season in the
latitude of New York City. The hot-air system works better with
compact square houses than with long, "rangy" structures. For a house
fully exposed to the northwest blasts, one of the other systems should
be considered.

Perhaps the next most popular arrangement is a sectional cast-iron
hot-water heater, with a system of piping to and from radiators in the
rooms to be heated. Hot-water heating has many advantages, some of
which are the warmth of the radiators almost as soon as the fire is
started and after the fire is out; the modera