I love this subject. I discovered through experiment that the 
distribution of stores within a hive can greatly affect the weight 
derived by simply weighing one end of a hive and multiplying by 2. 
Better to weigh both sides and add them together.

I think the basic manometer approach is the way to go because it's 
simple and in theory has no moving parts. My first proof-of-concept 
experiment involved a piece of surgical rubber tubing about 10' long 
filled with water with a glass pipette stuck in one end. The tubing was 
coiled into a loose spiral under a hive with the pipette taped 
vertically to a corner of the hive. It worked, after a fashion.

The Some time ago I searched the BEE-L archives and came up with this 
message which nicely describes a manometer for weighing hives made from 
a plastic bag used in those cardboard wine boxes:

http://listserv.albany.edu:8080/cgi-bin/wa?A2=ind9610B&L=BEE-L&P=R5349&I=-3

George-

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