real thing. My front pages, again intended for the lengthwise fold,
are shown as [15].
Track identification maps
I mentioned that these are essential for those doing switching, and
although previous versions of my model timetable included hand-
drawn examples similar to [10], I wanted to go in a little different
direction for this new timetable. My first idea was to followwhat
Southern Pacific did in later years, an arrangement they called
SPINS, which stood for Southern Pacific Industrial Numbering
System. Unfortunately, the earliest one I have found for my area of
the SP Coast Line is dated 1972, just about 20 years after my mod-
eling date, so only of limited factual use, but suggestive of method.
Briefly, the SPINS concept was to define zones all over the railroad,
identified by two-digit numbers; identify all tracks in that zone by a
second two-digit number; and then call out individual spots on that