"Greg" wrote in message
...
Actually my buddy told me I'm in error. They calculated each jug to
support
25
pounds, so 4 jugs to 100 pounds. I believe Dolly only has two.


A pint's a pound the world around. A gallon of sea water is about 8
pounds. You
will get a significant part of that in bouyancy with a jug of foam.
So about 13 jugs for 100 lbs.

bouyancy is determined by how much water is displaced and a foam filled
gallon jug displaces just as much as one that isnt filled when submerged,
assuming no crushing occurs. the only reason to fill them with foam is for
durability.

randy