Readers respond other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific conceptsAn assistant at my optician told me that over time the lenses of sunglasses wear out and no longer protect the eyes. She advised me to immediately salvage rid of my 1976 Ray-Bans (lenses by Bausch & Lomb) and replace them with something expensive. Is she right,or just trying to blind me into another sale?Martyn Day, TwickenhamContinue reading...
Source: theguardian.com