Error "send expects scriptable object..."

[#1]

HI Everyone, I'm trying a very simple script that is meant to function within a data table, in other words, I have the data table allready and have created a script within it (not sure is that's relevant but thought I'd specify...). 
I'm trying to retrieve the spec limits from column7 below and getting this error everytime:

"Send expects scriptable object in access or evaluation of 'Send', Eval Exp(":" || cols[7]) << /*###*/ Get Property ("Spec Limits") /*###*/"

The code I'm using is here:

Names Default to Here(1); //This enables any variables to remain local to the script and not interact with any
                                          //pre-defined jmp environment variables.
Delete Symbols();             //Removes the values of any global variables already defined in the jmp enviroment so that
                                         //they don't override any local variable you may define in your script.
clear log ();
cols = Data Table(1) << Get Column Names( numeric, continuous );
Q = Eval Expr(":" || cols[7]) << Get Property( "Spec limits" );

[#2]

Here is one way of doing what you want using the Column() function.

Names Default To Here( 1 ); //This enables any variables to remain local to the script and not interact with any
//pre-defined jmp environment variables.
Delete Symbols();             //Removes the values of any global variables already defined in the jmp enviroment so that
//they don't override any local variable you may define in your script.
Clear Log();
cols = Data Table( 1 ) << Get Column Names( numeric, continuous );
Q = column( char(cols[7])) << Get Property( "Spec limits" );