The Anatomy of a Mattress

Pocket Coil or an encased coil, or encased spring,(most commonly known in North America as “pocketed spring”) is a component part of a mattress in which each coil is separately wrapped in a textile material. Encased coils may also be generically referred to as Marshall coils or wrapped coils. Marshall coils were created by English-born James Marshall in 1900, when he settled in Canada. In 1901, he sold the rights to this design to English mattress maker VI-Spring. He received a Canadian patent for his unique invention: Marshall established the original Marshall Mattress factory to produce his mattresses in Toronto, Ontario. Marshall conceived of a mattress whereby internal independent springs would provide both support and comfort within the mattress itself. Marshall produced pre-compressed cylindrical coil springs, each sewn inside an individual cotton fabric pocket, which provided uplifting support on its own. When fitted together, the coils became an independent suspension system that contoured to each person’s form and weight, providing unsurpassed support and comfort. When upholstered, a finished Marshall mattress not only reduced physical pressure under the sleeper, but actually relieved it as well. Consequently, Marshall’s pocket spring-filled mattress system became the original worldwide standard for spring-filled mattress construction and would continue to shape the next century in mattress design. Many other manufactures also now use the pocketed coil, but each manufacturer is different.