On Sun, 8 May 2011 10:34:48 +0100, DerbyBoy wrote:

What about a long cylinder full of Mercury (see other posts about
mercury container!)

B-)

Mercury is only 2g/cm^3 denser than Lead so the added agro is
probably not worth it. Hg 13.5g/cm^3, Pb 11.3g/cm^3.

Gold would be better 19.3g/cm^3 that's higher (just) than uranium.

--
Cheers
Dave.