Rochester Telephone Book for 1910

The Monroe County Public Library has an ongoing project to digitize local books for the area.  This is a part of its Local History work.  Among the newest books to be digitized are the Bell Telephone Directory for 1910 and 1912 and on page 68 of the 1910 version we find my great-grandmother:

Eagan, Patrick Mrs., Res. 108 Atkinson . . . . . . Main 690

She is also found in the 1912 version on page 70 at the same address and the same number.  I suspect that numbers that have a number followed by a letter were party line.  Those without a letter were single lines.  I remember that our number on Flint Street was Genesee 5577-M.