Probably a typo in your post, but a typo would cause this sort of problem:
"Materia::Variable::Pressure". I think you want "Material::Variable::Pressure".

Also, have you considered putting expressions into a hash building expression? I find that style much more readable (especially after reading large amounts of Data::Dumper output). 
my $hydrogen = { element => { Z => 1,
                  mass => ...,
                },
         name => { default => 'Hydrogen',
               'en-CA' => 'Hydrogen',
             },
         symbol => { ... },
         boilT => ...,
           };

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In reply to Re^5: OO: short memory? by plobsing
in thread OO: short memory? by Anonymous Monk

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