5 OCTOBER 2002, Page 64

Q. In the course of a typical week I normally

spend a good deal of time travelling around the country by train. During these trips I frequently find that my mobile telephone has run short of battery because of the high volume of calls I have to make. Being on a train I have no means of recharging it. I might add that I am always at pains to avoid offending other passengers. and therefore make a point of standing in the corridor between compartments to make and receive calls on such journeys. Something which has often caught my eye is the mysterious empty plug socket that can be seen lurking at the back of the luggage racks on intercity trains. Can you tell me whether it is legally and/or practically acceptable to plug one's charger into this socket on a long journey?

Dorchester, Dorset A. The purpose of these mysterious empty sockets on intercity trains is to enable service engineers to plug in vacuum cleaners when the trains are safely berthed. Sadly the sockets cannot be employed for this useful end as power surges while the train is in motion would cause a mobile to 'blow' altogether. The better option is to precharge a spare battery at home and carry it on your person.