Letter books

I have some letter books, those that were used in the first half of
the 20 century. They have in the first part an index and the second
empty pages of copying paper, I would like to know if somebody can
explain how they were used, I haven't found any explanation on how
letters were copied to them. Were used with carbon copy sheets? or
other media? How? Thanks for any explanation,

Andres Robayo
+57 1 862 0849
Bogota, Colombia


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                  Conservation DistList Instance 18:21
                 Distributed: Tuesday, November 9, 2004
                       Message Id: cdl-18-21-007
                                  ***