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  I haven't seen the Hyde and Company maps, but I wouldn't be too quick to
dismiss their importance to real estate salemen, particularly those
specializing in commercial sales of vacant land, industrial/commercial
structures, or leasing of either -- not all realtors sell houses.  But
another group that might have a specific use for these property maps could
be title insurance companies (thus keeping the nomenclature "insurance maps"
partially valid?).  I have seen title companies using similar volumes
published by the Hopkins Company of Philadelphia for general reference, while
drawing their own detail maps for individual parcels and blocks.  This
identifies what may be the chief reason for the Hyde atlases: to provide the
general business community (and no sub-set in particular) with parcel-based
maps of their municipality containing more detail than available from common
street maps published by city directory companies, oil companies, etc.  That
is, the detail was to support a *particular* segment of the business
community, but rather to provide enough detail for *any and all* potential
users.
  Incidentally, the Sanborn  Company was recently written up in an issue of
Historic Preservation magazine, the publication of the National Trust for
Historic Preservation (I looked for the exact citation, in vain, but it was
the summer or fall of 1993 sometime).
  The H-URBAN discussion list recently had a thread about Sanborn maps and
their research value, which should be available in its archive.  Inquire at
the list's marvelous co-moderator Wendy Plotkin ([log in to unmask]
psu.edu) for details.
Bill Barrow
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