INTRODUCTION. x j x 
the continuance of the Expedition, but since its return, while acting 
in concert with me in preparing the illustrations of the Narrative for 
the press. I cannot but congratulate myself, that we should have been 
so fortunate in having one attached to the Expedition so well adapted 
to encounter, and from his former experience to overcome, the difficul- 
ties we have had to contend with in the progress of the publication. 
The country is particularly indebted to the Joint Committees of two 
successive Congresses* who have had the execution of the law for the 
publication of the results of the Exploring Expedition entrusted to 
them. They have afforded me all the assistance I could desire ; and 
through the facilities obtained, I have been enabled to bring the Nar- 
rative to completion at a much earlier day than I at first anticipated. 
To the Hon. Benjamin Tappan especially, I feel under obligations 
for the great interest he has ever taken in the Expedition. The law 
for the publication was originally reported by him; he was at an 
early day appointed the agent of the Committee to superintend the 
whole work in its progress; and it has afforded me great pleasure, as 
well as satisfaction, to co-operate with one so competent to the task. 
I am aware that some dissatisfaction was occasionally felt at the 
outset by a few of the naturalists, because they were not allowed all 
the opportunities they desired of making investigations. It was not 
* Members of the Joint Committee on the Library of Congress, at the Second Session 
of the Twenty-seventh Congress : 
SENATORS. REPRESENTATIVES. 
Hon. William C. Preston, Chairman, Hon. Joseph L. Tillinghast, 
Benjamin Tappan, John B. Aycrigg, 
Rufus Choate. Thomas D. Sumter. 
At the Third Session of the Twenty-seventh Congress : 
SENATORS. REPRESENTATIVES. 
Hon. William Woodbridge, Chairman, Hon. Joseph L. Tillinghast, 
Benjamin Tappan, John B. Aycrigg, 
Rufus Choate. Thomas D. Sumter. 
At the First Session of the Twenty-eighth Congress : 
SENATORS. REPRESENTATIVES. 
Hon. Rufus Choate, Chairman, Hon. Edmund Burke, 
Benjamin Tappan, George P. Marsh, 
John M. Berrien. William B. Maclay. 
