Programaticlly adding to recipients list

Could someone please provide an example of programatically creating a list
of recipients?

For example, let's suppose I have a TMemo with one email address per line.

How would I add those addresses to a TIdMessage ?

For i:= 0 to pred (memo1.lines.count) do begin
  st := memo1.lines [i];
  ?????
end;

Thanks,

Mac