At 20:01 8/18/99 -0400, David Beierl wrote:
actually going on.  Simply adding water so that it is at least say 15" deep
>in each arm, and there is at least 15" of tubing above the water in the arm
>that's not connected to the gas, then applying pressure and putting a ruler
>btw the upper and lower menisci is all that's necessary.

Well I fell into the same hole here -- 7-8 inches of water on each arm, and
the same clear in the outer arm, is plenty.  The only aim is to 1) not blow
the water completely out of the descending arm and 2) not overflow the
ascending arm.

:-/
david

David Beierl - Providence, RI
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"