XIL—REPORT OF PROGRESS OF AN INVESTIGATION OF THE 
CHEMICAL COMPOSITION AND ECONOMIC VALUES OF FISH 
AND INVERTEBRATES USED FOR FOOD. 
UNDERTAKEN FOR THE UNITED STATES FISH COMMIS- 
SION. 
Bye Wi! Ov Atwater, Pa. D:, 
Professor of Chemistry, Wesleyan University, Middletown, Conn. 
Sir: Herewith I have the honor to transmit a report of progress of 
the investigation of the chemical composition and economic values of 
fish and marine invertebrates used for food, which has been in process 
for some time past in this laboratory, under the awspices of the Smith- 
sonian Institution and the United States Fish Commission. 
This report includes analyses of fifty-one samples of fish and twenty- 
five of oysters, lobsters, and other invertebrates. It is divided into 
three parts. 
Part I gives account of analyses of fish, including description of sam- 
ples, tabular statements of results, and methods of analyses. 
Part Il gives similar data regarding invertebrates. The investiga- 
tion it describes was undertaken at my suggestion by my assistants, 
Messrs. Woods and Beamer, who have also shared in the investigations 
of fish, and who report those upon invertebrates. 
Part III summarizes the more immediately practical results of the 
work, especially in its relations to the nutritive values of the samples 
analyzed, the detailed account of the more abstract investigations being 
reserved for another occasion. 
Permit me to say that I regard this as only the beginning of a much 
needed research. Work in this line, rightly conducted, may, unques- 
tionably grow into an inquiry of the greatest value. 
To obtain the best results the investigation should, it seems to me, 
be pushed in two directions, namely, toward the study of— 
1. The chemical constitution of the tissues and fluids of the bodies of 
the animals. 
2. Their economic values, especially for food. 
The more abstract study of the chemical composition of the substances 
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