May 17, 1901.] 
marvel because of the great pyramids, and 
they have always been considered one of 
the wonders of the world; but, reckoned at 
the present cost of masonry, a dozen such 
pyramids could be built for the expense in- 
involved in the Nicaragua Canal. And 
when it shall be built the engineer may 
well improve the great waterways of the 
interior and build fleets of steel barges 
that can withstand the sea, so that our 
products can be sent without tranship- 
ment from our inland cities to the western 
coasts of the Americas. Another product 
of the century of significant import is Port- 
land cement. With the aid of the chemist 
this material has been so improved and 
made accessible that now the artificial 
stone made from it is most widely used and 
is superior to most natural ones. Further- 
more there is the unequivocal indication 
that, in combination with the all-important 
steel, many classes of structures of superior 
characteristics will be designed. Already 
there have been built many steel and con- 
erete bridges which are a hundred feet in 
span and more, and for the Memorial 
Bridge at Washington, maximum spans of 
this construction are planned to be 192 feet 
each in length ; while the engineer who de- 
signed it considered perfectly practicable 
an alternative plan of similar arches 283 
feet in length. Arches of such majestic 
span are among the imminent constructions 
of the engineer. 
A half-century ago Macaulay said, 
“Those projects which abridge distance 
have done most for the civilization and 
happiness of our species.”” And yet, since 
then, transportation facilities have in- 
creased many-fold, the first ocean cable 
had not been laid, nor was the telephone 
in use, nor other distance-annihilating in- 
ventions made. The attainment of results 
both definite and valuable has been in con- 
stantly accelerating ratios through all the 
broad field of endeavor which marks the 
SCIENCE. 
775 
domain of the engineer, viz., the ‘ direc- 
tion of the great sources of power’ and the 
development of the boundless resources of 
materials in nature to the use and conven- 
ience of mankind. The effect and value of 
this art pervade all lines of human inter- 
est and of contact, whether following 
Macaulay’s idea of potentially bringing 
peoples nearer together or in the way 
(largely developed since his day) of ren- 
dering it possible to make life more 
thorough and intense by the concentration 
of power and of effort in great centers of 
activity, which is made possible by engi- 
neering structures and developments such 
as the towering office and industrial build- 
ings of the last score of years; the tremen- 
dous concentrated power in steam and 
electric machinery of the present; the 
penetrating circulation of life-bringing, 
waste-removing water, ministering to our 
cities as does the blood to the body ; and 
other examples of almost infinite variety 
which would cause amazement were they 
not so common now. 
The glory and the power of the civiliza- 
tion of to-day result from the concentration 
of forces, both human and material, com- 
manding the resourcefulness of mankind, 
applying the principles and discoveries of 
pure science, and developing the resources 
of nature for this purpose ; and such is the 
degree of successful adaptation already 
reached, that the span of life of man poten- 
tially surpasses the millennial existences of 
legendary times. ‘Better fifty years of 
Europe than a cycle of Cathay.’ And the 
crowning glory of the measure of achieve- 
ment thus far reached is that its inspiration 
is the welfare of the race. 
J. L. Van Onnum. 
WASHINGTON UNIVERSITY. 
MONAURAL LOCALIZATION OF SOUND. 
In the Psychological Review for May, 1901, 
occurs a detailed account of an investiga- 
