Whether the window admits the displacement at each end, taken apart.
The two ends answer different questions. The onset, with the kind,
decides identity: whether the two copies read one command. The end
decides duration: whether the same command was lengthened or
shortened. A collation joins two readings only where both admit, so a
separation may be the work of either, and an editor looking at one
wants to know which.
A difference at the end alone has at least three causes and only the
first is an editorial act. A punch may genuinely have been lengthened
or shortened. A chain of punches, bridged to keep the paper strong,
may have been read as one perforation on one copy and as repeated
notes on the other, which Phillips names as a common error of roll
scanning and which runs in both directions (p. 173). Or a reading may
report something other than the punched slot, as a pneumatic reader
reports how long a valve stayed open. Long held notes are where the
second is likeliest, since that is where the chains are.
Whether the window admits the displacement at each end, taken apart.
The two ends answer different questions. The onset, with the kind, decides identity: whether the two copies read one command. The end decides duration: whether the same command was lengthened or shortened. A collation joins two readings only where both admit, so a separation may be the work of either, and an editor looking at one wants to know which.
A difference at the end alone has at least three causes and only the first is an editorial act. A punch may genuinely have been lengthened or shortened. A chain of punches, bridged to keep the paper strong, may have been read as one perforation on one copy and as repeated notes on the other, which Phillips names as a common error of roll scanning and which runs in both directions (p. 173). Or a reading may report something other than the punched slot, as a pneumatic reader reports how long a valve stayed open. Long held notes are where the second is likeliest, since that is where the chains are.