Thanks for the feedback, ya'll. As for which hive the swarm issued from...I was standing within 5' of it when it started and watched the bees come out of the hive on the right. They swirled in the air for several minutes with a mass activity in front of the hive. Then bees from the swirling swarm started landing on the hive on the left until the entrance and the sides adjacent to the entrance was covered in bees. Many of the freshly arrived (though short traveled) bees quickly entered the hive leaving a small contingency on the outside. Within and hour all seemed normal once again. The swarm definitely came out of the righthand hive and entered the lefthand one. It made me raise an eyebrow, for sure....but very neat to experience.

Here's a shot of the two hives taken this afternoon...I *think* I measured 4' between them when I initially placed the blocks.

Here is a shot of the "receiver" hive probably 20 minutes after the swarm landed/entered...

Beats me, I'm just glad I didn't have to hive another swarm.

Ed