Blue Badge Tourist Guide Richard "Rick" Jones explores sites in London with links to Lionel Lockyer, a physician espousing questionable remedies in the plague era. According to Chambers dictionary, a quack is ‘someone who claims, and practises under the pretence of having, knowledge and skill that he or she does not possess.’ A quack doctor, then, is a fraud.

Until perhaps the last thirty years, there was some truth in the belief that north of the River Thames was smart, wealthy and desirable but south of the river was the haunt of thieves, vagabonds and only approached with caution. Even London’s cabbies were reputed to be reluctant to go south of the river at night. Times have changed. Peckham and Brixton as well as Clapham are now achingly trendy and expensive and other areas like East Dulwich and Forest Hill are up and coming.