20 PREFACE

work was largely made possible by the kindness of the Secretary of
the Treasury, who placed at the disposal of the state the valuable
apparatus in the possession of the United States Coast and Geodetic
Survey. Further observations will be made from time to time and a
second report will be published at a later date.

The co-operation of the Director of the United States Geological
Survey, by means of which increased topographic work has been
carried on from the first in different portions of the state, has been
a most important factor in the operations of the State Geological
Survey, and the data furnished has made possible the accurate platting
of the geologic boundaries. Direct co-operation along geological lines
has at the same time been of much importance to the successful pro-
secution of the state work.

Attention should also be called to the intelligent and valuable aid
which has been given. by Mr. A. B. Hoen of A. Hoen & Co., Litho-
graphers, of Baltimore, in the preparation of the lithographic maps
which add so much to the attractiveness of the volume.