Thanks for the replies.
"If you have Acrobat (not just Adobe Reader), you should have the "Recognize Text" feature, which will OCR the bitmaps and make them searchable."
Unfortunately Apple chose to provide only Adobe Reader with a new MacBookPro at £1500.
I don't want to pay £131 for Acrobat, just yet.
"Have a look at this service - it might help you
I did download that but could not get it to work.
I will try again in 2014.
It may seem strange but when I bought my G4 iMac in 2002 or so it came supplied with an OCR application, free of charge - part of the Classic suite.
Apple seem to have perfected the art of selling less product for more cash.
Likewise that G4 package included a database app and a spreadsheet app in Appleworks - all for 'nothing added to purchase price'.