PACIFIC EXPLORATION: W. M. DAVIS 
391 
THE EXPLORATION OF THE PACIFIC 
By W. M. Davis 
DEPARTMENT OF GEOLOGY AND GEOGRAPHY. HARVARD UNIVERSITY 
Read before the Academy. April 17. 1916. Received May 25. 1916 
A voyage across the Pacific, such as the Shaler Memorial voyage 
that I made two years ago, gives a traveller time on the free days be- 
tween groups of islands to think of many problems, old and new; and 
thoughts of unsolved problems tend to run on into dreams about their 
possible solution. Even after returning home, the dreams continue in 
intervals of rest between spells of work on the results of the voyage; for 
just as the unrecorded facts that one so often finds while in the broad 
ocean impress their observer with the great volume of work still to be 
done, so the records of earlier work which one reads in a home library 
too frequently disappoint him by their incompleteness, their insuffici- 
ence; thus at home and abroad, the wish of a fuller accomplishment is 
repeatedly present. 
The insufhcience of earlier work and hence the abundant opportunity 
for new work was first borne in upon me in connection with the old 
problem of coral reefs, to the investigation of which my own voyage 
was directed. This does not mean that a later traveller is ungrateful 
for what his predecessors have done, but that he need not carry gratitude 
to the point of being thankful to them for having left so rich and ripe 
a harvest to be gathered by their successors. Nor would a reference 
to the insufhcience of earlier work be just, if the insufficiency concerned 
matters or methods unknown in earlier years. But when their insuffici- 
ency concerns truths so well established as the geological principle of un- 
conformity and the physiographic principle of embayed shores, known 
and understood, one for a century, the other for half a century past, and 
directly pertinent in the problem of coral reefs, one must wonder in how 
many other directions the work thus far performed in the Pacific is 
incomplete. A student of coral reefs today cannot avoid regret at the 
repeated failure of earlier observers to note matters so manifest as the 
embayed shore lines of the central islands within barrier reefs, and the 
unconformable contacts of many fringing and elevated reefs with their 
deeply eroded foundations, inasmuch as these simple and evident 
relations immediately demonstrate submergence in association with 
reef formation, and thus contribute vahantly to the solution of the old 
coral-reef problem. With the regretful discovery of such oversights 
with respect to one's own special subject in the records of the most 
famous Pacific expeditions, one cannot avoid suspecting the occurrence 
