After World War 1, the population of feral dogs in some Northern English towns was so high that extreme measures were taken to catch them. The dog catchers of the day took to wearing specially padded trousers which they would dangle shanks of ham from and this would attract the feral muts as they ran through the streets. Eventually the catcher would lead them down a dead end where they would be captured and sold to the dog food factory. This led to all dog catchers being referred to as 'ham leggers' and the name persists to this day