padfootandprongsftw:

tswiftvfdpotterclan:

sammit-damn:

buckkybbarnes:

wait

hogwarts was established in the 10th century

but sinks were not invented until the 18th century

so how did salazar slytherin mark the chamber of secrets with a form of indoor plumbing which would not be invented for another 800 years 

?????

*looks for historical inconsistencies in a book about wizards*

This was actually answered on Pottermore! Tom Riddle was not the only one of Slytherin’s descendants to know about the Chamber, or to open it. Throughout the centuries, it has been opened a number of times, and Slytherin’s descendants have heard the Basilisk, spread rumours, and kept the Chamber hidden. When plumbing came to Hogwarts, Corvinus Gaunt, a descendant of Slytherin’s who was attending Hogwarts at the time, was responsible for hiding the entrance to the Chamber; previously, it had been a concealed trapdoor leading to a series of magical tunnels. When a girls’ bathroom was built above the entrance, he made sure that the entrance was still hidden but also accessible to Slytherin’s descendants. 

this is important information