To confirm whether it is a Bramah (or Bramah type) lock is easy enough. Such locks have a round escutcheon which protudes through the wood, rather than a keyhole cut in the wood. In the centre of the round escutcheon should be the keyhole - also round usually around 5mm in Diameter with a small rectangular cut out at the bottom.

If the above is OK then shine a small torch into the keyhole and you should see a small round pin in the centre with a number of flat steel plates radiating from it like the spokes on a wheel.

Given that it is a tantalus it is most likely to have a Bramah lock.

As to getting it open & having a key made you can of couse go to Bramah in london, but there is an easier & far less expensive option.

Contact Mostly Boxes in Eton - they are in the High St and ask the owner there (gary) to put you in touch with David Evans - he will be able to open it and should the key not be inside - make a new key for you.

There is one further option - the Bramah mechanaism was popular in France & Belgium, I would have thought that you could find a locksmith familiar with it - I would suggest that anyone who specialises in safe work would be best placed to help as the Bramah mechanism was widely used on safes.

Best of luck & perhaps you could post your findings.

Paul