PREFACE. 
By E. C. Eckel. 
The following report on the clays of Arkansas was prepared by 
Prof. John C. Branner, while State geologist of Arkansas, for pub- 
lication by the State Survey. The work of the organization was 
unexpectedly discontinued, leaving no provision for the publication 
of this report. Under the circumstances Professor Branner offered 
the manuscript for publication as a bulletin of the United States Geo- 
logical Survey. As some years have elapsed since the original 
preparation of the manuscript, it has been necessary to bring up to 
date, so far as possible, the commercial and statistical data included 
in the report. Advantage has also been taken of recent Survey 
work in Arkansas to introduce later observations on the geology of 
certain districts. Mr. A. F. Crider has accordingly revised the sec- 
tions on the geology and clay industries of the southeastern coun- 
ties, while Mr. E. F. Burchard has revised the discussion of the 
Paleozoic clays and of certain areas in northwestern Arkansas, with 
a view chiefly to bringing the nomenclature into accordance with 
present Survey usage. 
