The concept of waxed cotton was originally developed in the early 15th century by sailors. Scottish North Sea herring fleets operating from east coast ports began treating flax sailcloth with fish oils and grease in an attempt to water proof their sails, keeping them light and efficient. Remnants of these sails were used as capes to withstand the high winds and sea spray, keeping the sailors warm and dry. These capes were the forerunner to the fisherman's slicker.
Sailcloth evolved and by the mid 1850's, to be made from lighter weight double fold cotton yarns, treated with linseed oil.
Early Royal Navy sailing ships and tea clippers were amongst the first to use these light weight cotton sails, famously "The Discovery", that still sits in Dundee's port today.
Linseed oils yellow and stiffen through weathering. Through this oxidation process, the oil would eventually lose its water proofing qualities, hence the development of alternative water proofing compounds. In the years that followed, various treatments were applied to cottons in an attempt to find the most effective, and the combination of densely woven cotton, impregnated with a paraffin waxed coating proved most successful. These fabric constructions are still used to this day and the wax treatments have been developed to give longer lasting, waterproofing finishes.