Thank you all for your replies.  This group is great to come to the
rescue of a newbie like me.  I believe the consensus is that these are
nodal holes.

Okay, here is the other side of the question: Did Seeburg intend for
these pipes to be drilled, or did someone else try to make these pipes
do something that they were not intended to do?  Should I plug them or
should I leave them alone?

Thanks,
Phil Housh

 [ Maybe the pipes weren't built by Seeburg; only an experienced
 [ restorer could determine this.  If the pipes aren't original
 [ then they probably were made for a different wind pressure.
 [
 [ You wrote in 020110 MMD, "Some of them have been covered with
 [ masking tape, some have been covered with what looks like Scotch
 [ tape, and still others have been left uncovered."  From your
 [ description, a previous rebuilder didn't know how to modify salvaged
 [ pipes for a different wind pressure.  (A good tech doesn't leave
 [ masking tape exposed on a wood surface! ;-)
 [
 [ You must decide whether to throw out the pipes or fix them so they
 [ sound like good Seeburg pipes _should_ sound.  It's a tricky task;
 [ seek assistance from a pipe organ technician.
 [
 [ -- Robbie