‘Further’ versus ‘Farther’
When do you use ‘Further’ versus ‘Farther’? The Grammar Ninja says you can look up the difference if you want, but don’t sweat it too much because, as Grammar Girl points out “…the Oxford English Dictionary and other sources say that, in most cases, it's fine to use “further” and “farther” interchangeably, especially when the distinction isn't clear.” However, a quick tip is to think of ‘farther’ as only referring to distance whereas ‘further’ can also mean ‘additional’ or ‘more’.
“Sir Shag-a-lot, how much farther do you think your turtle-sized dong grows when erect?”
“Why, a good ten inches, m’lady.”
One further example of a creature with an enormous dong is the African elephant, with an average penis size of around 6 feet, 5 inches.