AuGusT 16, 1918] 
the New York State Cabinet of Natural His- 
tory. His next three articles have been noted 
above, relating to Ohio geology and the ancient 
beaches. From 1871 his papers are mostly in 
description of features of the western country. 
The most important of his earlier papers is the 
report on the Henry Mountains, published 
1877. In this classie paper he described a new 
type of mountains, now fully recognized. 
These were originally domes, or areas of sedi- 
mentary strata lifted by the injection of lava 
from beneath. Quoting his own description, 
page 19: 
The lava of the Henry Mountains behaved dif- 
ferently. Instead of rising through all the beds 
of the earth’s crust, it stopped at a lower horizon, 
insinuated itself between two strata, and opened 
for itself a chamber by lifting all the superior 
beds. In this chamber it congealed, forming a 
“massive body of trap. For this body the name 
laecolite (cistern-stone) will be used. 
In later years the name has been changed to 
laccolith. Subsequent erosion of these uplifts 
by doming has often destroyed the arching 
form or obscured the primitive shape and ex- 
posed the injected igneous heart. The latter 
part of this book is a discussion of land sculp- 
ture. In this statement of the principles of 
erosion and the origin of topographic forms he 
shares with Newberry and Powell the honor of 
a pioneer. 
Probably his most famous writing is the work 
on Lake Bonneville. This is the initial volume 
of the series of quarto monographs published 
by the National Survey, and bears the date 
1890. This describes the wide expanded prede- 
cessor of the present Great Salt Lake, which 
existed in glacial time when humidity and rain- 
fall of the Great Basin produced the vast lake 
which overflowed northward to the Columbia 
River. Great Salt Lake is only the saline 
remnant of that desiccated fresh-water body. 
This handsome quarto volume contains a 
chapter on “Topographic Features of Lake 
Shores ” which is the classie writing on shore- 
line topography. 
It is interesting to note that he published no 
articles relating to the Rochester region until 
-after his long period of western exploration. 
SCIENCE 
153 
His first publication in reference to the On- 
tario basin was in 1885, on the Iroquois shore- 
line; although he then called it simply the old 
shore-line of Ontario. Between then and 1891 
he published six papers on the Pleistocene fea- 
tures or glacial history of the Ontario basin; 
and one on the sink ridges near Caledonia. 
From 1892 to 1900, eight years, his list of 
writings is forty; covering a wide range of 
subjects in geology. Of these eight related to 
western New York. From 1901 to 1905 twenty- 
five titles are on record, of which only two 
concern western New York. During 1906 and 
1907 he published nine articles, one being on 
Niagara. In 1908 only four articles, including 
another on Niagara, are recorded in the bib- 
liography. Since 1908 only five titles are cred- 
ited. Altogether this makes 156 titles, of 
which 18 relate to the geology of western New 
York or the Ontario basin. 
The few papers published in later years is 
explained by his poor health, due to a slight 
stroke of apoplexy. After this time by very 
eareful living he was able to do some work in 
a deliberate way. His latest study was the 
transportation of detritus by streams, with 
reference to hydraulic mining in California. 
This work, spread over several years, was pub- 
lished last year, being his last publication. It 
is entitled “ Hydraulic-mining Debris in the 
Sierra Nevada,” and is Professional Paper 105 
of the Survey list, forming a quarto of 154 
pages, with numerous maps and reproduction 
of photographs. 
Dr. Gilbert’s only writing for school text- 
books in his “ Introduction to Physical Geog- 
raphy,” in collaboration with Professor A. P. 
Brigham. This was published in 1892 by D. 
Appleton and Company. 
Geology is so broad and comprehensive and 
so inviting in many directions that some men 
with active minds and lively interest scatter 
their studies over diverse fields. Dr. Gilbert 
more wisely confined his work to physical geol- 
ogy, especially geodynamics, in which he was 
recognized as a master. He published prac- 
tically nothing in biologie geology or paleontol- 
ogy; and almost nothing in stratigraphy and 
petrology. 
