The files:

9129CATD.DDF  9129DDOM.DDF  9129DQHL.DDF  9129IREF.DDF  9129STAT.DDF  
9129CATS.DDF  9129DDSH.DDF  9129DQLC.DDF  9129LDEF.DDF  9129XREF.DDF  
9129CEL0.DDF  9129DQAA.DDF  9129DQPA.DDF  9129RSDF.DDF  
9129DDDF.DDF  9129DQCG.DDF  9129IDEN.DDF  9129SPDM.DDF

constitute a United States Geological Survey (USGS) 7.5-minute Digital 
Elevation Model (DEM) for the Mt. Washington quandrangle.  This data set
covers an area of roughly 14,000-by-10,000 meters in the White Mountains
of New Hampshire, USA, with elevations posted every 30 meters.  The data
are referenced to Universal Transverse Mercator (UTM), Zone 19, in the
North American Datum of 1927.  Horizonal and vertical units are both
meters.


Self-Documentation
------------------
This data set is formatted according to the Spatial Data Transfer Standard
(STDS) Raster Profile.  Its self-documentation includes the following
information:

            Filename: '9129CATD.DDF'
               Title: 'MOUNT WASHINGTON, NH - 24000'
           ProfileID: 'SDTS RASTER PROFILE'
      ProfileVersion: 'DRAFT VERSION JULY 1997'
             MapDate: ''
    DataCreationDate: '19980811'
     HorizontalDatum: 'North American 1927'
        MapRefSystem: 'UTM'
          ZoneNumber: 19
         XResolution: 30
         YResolution: 30
        NumberOfRows: 472
        NumberOfCols: 345
     HorizontalUnits: 'METERS'
       VerticalUnits: 'METERS'
        MinElevation: 367
        MaxElevation: 1909


General Information on USGS DEM Products
----------------------------------------
http://edc.usgs.gov/products/elevation/dem.html


README File from the SDTS Data Set
---------------------------------------------------------------------------
README File:      SeriesID: 7.5 Minute DEM             September 2, 1997

Welcome!
This directory contains a Spatial Data Transfer Standard (SDTS), 
Raster Profile (RP) compliant transfer, produced by the National
Mapping Division of the United States Geological Survey (USGS).

PURPOSE OF TRANSFER:
        This transfer was created as part of the SDTS Mass Conversion
        of 1997, when large amounts of the USGS digital archive were
        converted to SDTS/RP. This transfer was produced from the 7.5 min
        Digital Elevation Model (i.e. DEM).

STANDARD AUTHORITY:  
        FIPS 173: The Spatial Data Transfer Standard 
        Part 5: Raster Profile With BIIF Extension, Draft Version July 1997

ISO 8211 CONFORMANCE:
        All files with extension *.DDF are in the ISO 8211 file transfer
        format. All SDTS spatial addresses are expressed in two 32 bit 
        binary sub-fields defined by the ISO8211.  Files are Level 2 of
        ISO 8211.
 
CATALOG DIRECTORY MODULE xxxxCATD.DDF:
        Each transfer will contain this catalog directory module which
        contains a listing of every SDTS ISO 8211 file included in the
        transfer.  (xxxx indicates a four-character transfer base which 
        is common to all files in a transfer.)

IDENTIFICATION MODULE xxxxIDEN.DDF:
        This module contains information that describes the overall
        characteristics of the data in a transfer.

REFERENCES:
        "The Spatial Data Transfer Standard Mapping of the USGS Digital
        Elevation Model" -- draft document which describes SDTS transfers
        of DEM data, including detailed information on each module. The
        file can be downloaded from the SDTS ftp site in two formats:
        
   Word Perfect - ftp://sdts.er.usgs.gov//pub/sdts/datasets/raster/dem/demmap.wp
   Postscript - ftp://sdts.er.usgs.gov//pub/sdts/datasets/raster/dem/demmap.ps   
POINT OF CONTACT:
        SDTS Task Force               |  Information on SDTS is also
        U.S. Geological Survey        |  available on FTP site
        1400 Independence             |  sdts.er.usgs.gov (144.47.162.236)
        Rolla, MO 65401               |  Web: http://mcmcweb.er.usgs.gov/sdts
        E-MAIL: sdts@usgs.gov