EDDIE JONAS (HAS, July 13), makes a good point about the corrosion at the bottom of street lampposts and suggests a protective sheath.

Unfortunately, protective covers to protect steel have been tried since the days of Brunel and Robert Stephenson and they don’t work.

To prevent chemical attack whether from dog wee or the elements requires a perfect seal to totally exclude any contact with the steel, a sheath just encourages the chemicals and makes it harder to remove them.

Assuming that lampposts have to be steel (concrete serves very well) the best protection is galvanising which is the normal factory treatment and works for many years.

Galvanising does, however, wear away and the posts then need to be protected with a proper paint before significant rust sets in.

Our local council seems to have a touching belief in the longevity of galvanising, one lamppost is well rusted at the bottom, to the point where the concrete support has failed, I suspect that they will just leave them until they are beyond repair then change them.

Another instance of council short-termism?

Antony J Foster, Peterlee