xxiv           THE ICONOGRAPHY OF MANHATTAN ISLAND

and whom I had met in Holland during the preceding summer. This
letter informed me of Dr. Wieder's acceptance of the post of Assistant
Librarian in the library of the University of Amsterdam. Realising that
in this position he would have increased opportunities for cartographical
studies and more time for outside work, I wrote inviting him to undertake
for me certain researches in Dutch cartography, an invitation which he
readily accepted, and which led to a correspondence which has continued
at almost fortnightly intervals ever since.

These investigations, which at first occupied only occasional spare hours
in the collections of Amsterdam and The Hague, were continued during
the summer vacations and on special leave from the municipal and uni¬
versity authorities, and were eventually extended to cover, either by personal
visit or by correspondence, most of the important collections of Europe.

When these researches began, it was my intention to use Dr. Wieder's
reports in the preparation of my introductory chapter, but the pressure of
other work connected with the Iconography, and a growing realisation of
Dr. Wieder's far wider experience, as well as his closer proximity to the
sources of original information, soon led me to reverse this process, and to
ask him to submit his reports in the form of a constructive and connected
outline. Before this was completed, it became evident that it would be
impracticable to present the necessary facts and arguments within the limits
of a single chapter; and it was, therefore, determined to print the Cartog¬
raphy as an appendix, divided into several chapters. It later seemed de¬
sirable to include also in this appendix the material connected with the
Manatus Maps, the Castello Plan, and the Dutch Grants, as well as the
modern Real Estate and Insurance Plan of the Island; thus collecting into
a single volume practically all of the available early topographical data,
except the Landmark Map, which, unfortunately, could not be completed
in time. The Check-List of Early Newspapers was included here purely
because of space considerations.

When the preliminary report had been completed, and while such edi¬
torial modifications and additions as were suggested by my researches in
America were being made—in constant consultation with Dr. Wieder—the
great desirability of a personal examination of the Spanish archives became
apparent; and Dr. Wieder, finding it possible to procure from the city and
university authorities the necessary leave of absence, left Holland for this
purpose in February, 1914, and spent eight weeks in Spain, devoting a part
of this time to cartographical investigations for the Royal Dutch Geograph¬
ical Society.    As a result of these researches, such important new material