List of the Streets, Lanes, Alleys, Quays, Squares, Courts, Yards etc in the City & Suburbs of Dublin with reference to the other, with references for finding them in the map. (see here)

Page Streets
 1  Abbey Street - Borr's Court
 2  Boulton's Co[urt] - Elbow Lane Lit[tle]
 3  Elephant Lane - Marlborough St.
 4  Marrowbone L[ane] - Smock Alley
 5  Span's Lane - York St.
To quote the example from original directory : '...In the list of streets, Smithfield is situated near North King Street, and the letters of reference are 'E c d'. Turning to the plan and passing the eye downwards under the great letter 'E' and sideways opposite the small letters c and d you will nearly find the situation of the place you wanted.''

Or put another way, uppper case letter on an street entry indicates the column on the map, and the lower case letter the row. More than one of either letter means the street is across more than one row or column.