Before steel reinforced props were invented, timber props were used in construction.
At the beginning of the twentieth century, William de Vigier, born in Switzerland, invented the first steel adjustable prop after moving to London in 1935.
De Vigier named his invention the acrow prop after his solicitor Mr A. Crow.
The adjustable acrow prop could be used over and over again in construction, unlike the previous timber props which were cut specifically for the project being undertaken.