the first use of roller skates were said to be in london stage performance as early as 1743, with John Joseph Merlin claiming the first skate invention while living in London in 1760
They even featured during world war II when the U.S had the idea of using them to move infantry around Europe to save gas an idea that didn’t materialize 
In the U.S their first become a popular pastime in 1935 and when skating rinks playing disco music were introducetin the 1970s the hobby became all the rage.
For those of a certain age you may remember those have metal skates that attached to your shoes and adjusted as your feet grew
But you may not remember a metal object that came with these skates that most skaters wore around their neck
It is in fact key, and for those skating before 1970s it was essential to anyone with roller skates
Skates will be strapped to your shoe and the size could be adjusted using the skate key.
