22 
BULLETIN 102, UNITED STATES NATIONAL MUSEUM. 
under the exigencies of this dependence, as illustrated in the distribu- 
tive use of coal. But now a command of the electrical principle 
makes it possible to deal with energy freed from substance. This not 
only concerns coal by providing the means for extracting the energy 
at the point of production, instead of at the many points of use, to 
the gain of efficiency and the saving of transportation ; but it applies 
also to water power, a resource hitherto fallen into disuse because of 
its inability to cope with coal, but reintroduced by electricity upon 
more advantageous terms, to the practical gain of a new energy re- 
source. In spite of the fact that electricity has been in common and 
growing use in this country for many years, it has effected practically 
no change in the basic conventions of coal usage and has led to the 
development of a small fraction merely of the available water power. 
Since electricity has rehabilitated water power, thus making avail- 
able two energy resources where there was only one before, it is desir- 
able to determine the resource status of water power as compared 
point for point with coal power, for the two are coming, of necessity, 
into competition, and unless water power in its new habiliment can 
stand on a reasonably equal footing the outcome of the competition 
is bound to fall in favor of coal, as occurred before when steam power 
drove hydraulic power to the wall. In which event water power, in 
spite of its ethical advantages, would have no special signficance for 
the present. 
In respect to the size of the resource reinstated by electricity, there 
can be no fault to find. Efforts to determine its magnitude have led 
to estimates placing the possibilities of hydroelectric development 
in the neighborhood of 200 million horsepower, of which some 50 
million is capable of use without special provisions for storage. 1 
Expressed in another manner, the water power of the United States, 
converted to electrical energy, is more than capable of turning every 
industrial wheel and illuminating every street and building in the 
entire countrjL Also the resource is country-wide in distribution. 
(See fig. 1.) The apportionment amongst the various sections is by 
no means even, but the supply is more widely and equably spread 
than is the case with the coal fields ; and the regions distant from the 
sources of coal are all bountifulty favored with water power. Thus 
New England, the South Atlantic States, the Southwest, and the 
Pacific slope, together embracing over half of the potential water 
power of the country, are all practically without coal and bear testi- 
mony to this complementary distribution of power resources. (See 
Table 2.) This balanced occurrence has considerable bearing upon 
1 The discrepancies in the various attempts to inventory the water-power resources of 
this country are due to several qualifying factors, notably that of storage. Since the 
demand for power is commonly uniform the year round, the capacity of a given site for 
sustained effort is determined by the period of minimum flow. Accordingly, storage pro- 
visions doubling the flow merely during such periods will double the year-round capacity. 
