use  Geography::NationalGrid::IE;

       my $point1 = new Geography::NationalGrid::IE(
                GridReference => 'M 345132',
        );
        my $point2 = new Geography::NationalGrid::IE(
                Latitude => 53.8,
                Longitude => -7.5
        );
        print "Point 1 is " . $point->latitude . " degrees north\n";