The files are physically arranged by an index number assigned to each utility by the Railroad Commission and the PSC. The index numbers were used to track the receipt of documents from individual utilities as well as the distribution of correspondence, orders and decisions to utilities by the commissions. Decimal extensions to the index numbers generally indicate the acquisition of a utility by another, usually larger, utility operation.
For example, the Wood County Telephone Company and its acquisitions are listed as follows:
- #808: Wood County Telephone Company, 1907-1931
- #808.1: G.H. Munroe Telephone Company, 1920-1931
- #808.2: County Telephone Company (Wisconsin Rapids), 1929-1931
- #808.3: Chrystal-Saratoga Telephone Company, 1919-1952
- #808.4: Moccasin Creek Telephone Company, 1955
- #808.5: Advancement Telephone Company, 1956
- #808.6: Rudolph Telephone Company, 1908-1962
Researchers should be aware that utility names and index numbers are not always consistent. In addition, this collection is indexed in Series 1342, Indexes to Files, 1908-1955.
