The Prideaux Device was a unique speedloader developed by William De Courcy Prideaux for the Webley .455 caliber revolver.
US Patent 516,942
"Cartridge Packet Holder"
Filed by William De Courcy Prideaux, October 21st, 1893
US Patent 1,181,034
"Magazine for holding revolver-cartridges and for loading same into revolver-barrels."
Filed by William De Courcy Prideaux, July 20th, 1915