12 
PROCEEDINGS OF THE NEW HAVEN MEETING 
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The greatest problems of physical geology, according to Dutton (21), 
are : First. What is the potential cause of volcanic action ? Second. 
What is the cause of elevation and subsidence of restricted areas of the 
earth’s surface? Third. What is the cause of the foldings, distortions, 
and fractures of the strata? 
The first two of these he regarded as being without satisfactory expla- 
nation, and for the third he proposesd a solution in elucidating his 
theory of isostasy. After having shown that the contractional hypothesis 
is quantitatively insufficient and qualitatively inapplicable in explaining 
the folding of -the earth’s crust, he presented in a modified form and 
greater detail the theory propounded many years ago by Babbage and 
Herschel. It was pointed out that the unloading of the land by erosion 
and the loading up of the sea floor by deposition resulted in a force which 
tends to push the loaded sea bottoms inward upon the unloaded land 
horizontally — a force of the precise kind, that is wanted to explain the 
origin of systematic plication. 
This view of the essentially isostatic condition of the earth, for which 
he invented the name isostasy, has been in recent years most ably advo- 
cated, and in fact practically demonstrated, by Prof. John F. Hayford. 2 
Dutton began the study of the volcanic problems early in his geological 
career, and his first papers in the Geological Survey (4) pertained to 
volcanic products. In his study of the plateau region he had abundant 
opportunity to observe an extensive and profoundly interesting series of 
complete and dissected volcanic as well as plutonic masses. In 1882 he 
visited the Hawaiian Islands to study Kilauea, Manna Loa, and the other 
great volcanoes of that region (12) before beginning his survey of the 
great volcanic field of northern California and Oregon, where in 1885 h e 
made a special study of Crater Lake and recognized its similarity to the 
great calderas of Hawaii (18). 
He returned to military duty in September, 1890, and went to Central 
America and Lake Nicaragua. Hi^ 189_1 2 while on duty at San Antonio, 
Texas, he made frequent excursions to the volcanoes of Mexico. 
In 1899 he was recalled to duty in the office of the Chief of Ordnance 
in Washington, and on February 7, 1901, at his own request, was retired 
from active service. 
One of Dutton’s most notable contributions to science recognizes grav- 
ity as an essential factor in causing volcanic eruption. He was much 
2 The figure of the earth and isostasy. Coast and Geodetic Survey Report, 1909 ; also 
supplementary investigations. Coast and Geodetic Survey Report for 1910, and isostasy, 
a rejoinder to the article by Harmon Lewis. Journal of Geology, vol. xx, p. 562. Sept.- 
Oct., 1912. 
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