find a house wired for electric light; consequently the output of
current per foot of conductor is at the present time very low as
compared with the output of gas per foot of gas pipe in any of the
large cities. The expense of wiring (which must of necessity be borne
by the householder) is large, and it is often a barrier to the
adoption of electric illumination, but as the rule to wire houses
becomes more general, the output per foot of main will constantly
increase, and therefore the interest per unit of output per foot of
main will constantly decrease. This same rule will apply in the case
of expenses of taking care of and repairing the distribution system,
although to not so great an extent.

If you will take into account these various factors constantly
operating toward a reduction of operating and general expense cost,
and interest cost, the conclusion must necessarily be forced upon you
that the price at which current can be sold at a profit to-day is in
no sense a measure of the income per unit which it will be necessary
for central station managers to obtain in the future. In 1881-82 it
was difficult to make both ends meet with an income of 25 cents per
kilowatt hour, to-day there are many stations showing a substantial
return on their investment whose average income does not exceed 7
cents per kilowatt hour, showing 70 per cent. reduction in price in
less than two decades. How far this constant reduction in cost,
followed by a constant reduction in selling price, will go, it is
difficult to determine; but if so much has been accomplished during
the first 20 years of the existence of the industry, is it too much to
predict that in a far less time than the succeeding 20 years electric
current for all purposes will be within the reach of the smallest
householder and the poorest citizen? But few industries can parallel
the record already obtained. If you will trace the history of the