Vocal Voices

I get my weekly phone call from 42 and all I can hear in the background is Luke shrieking with laughter and saying......do it again James, go on do it again.......Quite what James was doing I am yet to find out, but you can bet your bottom dollar it was Mr Luke's idea

Tickling?

I would think it is more James falling off the bed, or pretending to knock something over.

Is that a clue - 'bottom' dollar?