PREFACE 
The present account of Alaska Glaciers, by G. K. Gil¬ 
bert, forms the third of the Harriman Alaska Expedition 
volumes and the first of the technical series. It is based 
on observations made by the author in the summer of 
1899, while a member of the Expedition, supplemented 
by information and photographs from various sources, and 
is illustrated by 106 text figures and 18 plates. The vol¬ 
umes on Geology, Cryptogamic Botany, Insects and Crus¬ 
taceans are to appear simultaneously with it. The vol¬ 
umes on Nemerteans, Oligochetes, and several other 
groups of Invertebrates, are ready for the press, and will 
follow as soon as they can be printed. The two volumes 
on Phanerogams, or flowering plants, are expected to ap¬ 
pear early in the year 1904. 
Acknowledgments are due the Canadian International 
Boundary Commission, the United States Biological Sur¬ 
vey, and, especially, the United States Geological Survey, 
for the use of photographs and other illustrative material. 
The editor wishes also to express his appreciation of the 
drawings prepared for this volume by Mr. W. E. Spader 
and Mrs. Louise M. Keeler. The frontispiece, plate xi, 
and a large number of the text figures are by Mr. Spader, 
while all of the chapter headings are by Mrs. Keeler. 
C. Hart Merriam, 
Washington, D. C. ( 
May 1, igoj. 
Editor . 
(v) 
