2 INTRODUCTION 



John Muir, of Martinez, California, Professor Benjamin 

 K. Emerson, of Amherst, Massachusetts, Dr. Charles 

 Palache, of the geologic staff of Harvard University, 

 and Mr. G. K. Gilbert, of the United States Geological 

 Survey. Before reaching the field of active work they 

 arranged a division of labor, so that each might give prin- 

 cipal attention to some special subject, with a view to 

 ultimate publication. Dr. Dall, already the foremost 

 authority on the physical geography, paleontology, eth- 

 nology and resources of Alaska, took charge of paleon- 

 tologic work; Mr. Muir, already distinguished as an 

 explorer of Alaska glaciers, continued his studies of their 

 general distribution and broader features; Mr. Gilbert 

 also gave principal attention to glaciers, but studied 

 especially their variation in size and the features bear- 

 ing on the interpretation of Pleistocene glaciation in 

 the eastern United States; Professor Emerson and Dr. 

 Palache undertook the observation of the sedimentary, 

 igneous and metamorphic rocks. 



The opportunities for geologic work were conditioned 

 by the mode of travel, the route, and the distribution and 

 duration of the various stops. The Expedition was essen- 

 tially a voyage, much the greater part of the two months 

 being spent on the ship and in motion. But the time 

 thus spent was not wasted. With unimportant exception 

 we were continually in sight of land, and the physio- 

 graphic expression of the country was the subject of 

 nearly constant study. Brief landings were made almost 

 daily, and in regions of special interest the vessel lingered 

 for periods of several days, while excursions were made 

 in launches and rowboats to various parts of the coast. 

 On such occasions the ship remained the principal base of 

 operations, but small parties operated independently with 

 the aid of camping outfits. In a number of instances local 

 studies were prolonged by leaving parties, either in camp 



