ter of the building has
been determined. One important feature, however, and one that has been
overlooked in many cases that we know of, is to so arrange the building
that switchboard sections and other bulky portions of the apparatus,
which are necessarily assembled at the factory rather than on the site,
may be brought into the building without tearing down the walls.

_Fire Hazard._ The apparatus to be housed in a central-office building
often represents a cost running into the hundreds of thousands of
dollars; but whether of large or small first cost, it is evident that
its destruction might incur a very much greater loss than that
represented by its replacement value. In guarding the central-office
equipment against destruction by fire or other causes, the telephone
company is concerned to a very much greater extent than the mere cost of
the physical property; since it is guarding the thing which makes it
possible to do business. While the cost of the central office and its
contents may be small in comparison with the total investment in outside
plant and other portions of the equipment, it is yet true that these
larger portions of the investment become useless with the loss of the
central office.

There is another consideration, and that is the moral obligation of the
operating company to the public. A complete breakdown of telephone
service for any considerable period of time in a large city is in the
nature of a public calamity.

For these reasons the safeguarding of the central office against damage
by fire and water should be in all cases a feature of fundamental
importance, and should influence not only the character of the building
itself, but in many cases the choice of its location.

_Size of Building._ It goes without saying that the building must be
large enough to accommodate the switchboards and other apparatus that is
required to be installed. The requirement does not end here, however.
Telephone exchange systems have, with few exceptions, grown very much
faster than was expected when they were originally installed. Many
buildings have had to be abandoned because outgrown. In planning the
building, therefore, the engineer should always have in mind its
ultimate requirements. It is not always necessary that the building
shall be made large enough at the outset to take care of the ultimate
requirements, but where this is not done, the way should be left clear
for adding to it when necessity demands.