The Materials And The Method
Plastic was the key material, and plastic in the late 1940s was a relatively new and versatile substance that a practical inventor could work with using household tools.
Modern plastics trace their commercial development primarily to the 1930s and 1940s. Nylon was developed in 1935. Plexiglas in 1936. Polyethylene in 1938. By the end of World War II, plastic manufacturing had expanded dramatically, driven by wartime production needs, and a range of plastic materials had become available outside of industrial contexts.
Blount worked with plastic by boiling water to soften it and shape it. This is a viable method for thermoplastic materials — plastics that soften when heated and harden when cooled. The specific plastic she used is not identified in the surviving accounts, but the method she describes is consistent with working with thermoplastic sheet or rod stock.
She shaped the plastic using a file — for removing material and smoothing surfaces. An ice pick for piercing or detailing. A hammer for forming. Dishes for molds — the domestic cooking environment provided both the materials for prototype components and the surfaces for shaping them.
The device needed to achieve several mechanical functions: storing food in a container that allowed delivery through a tube; a tube flexible enough to bend to the appropriate angle for the patient’s mouth; a mouthpiece that could be comfortably held in the teeth for the duration of a meal; a mechanism for controlling flow — specifically, allowing the bite-down motion of the patient’s jaw to trigger delivery of a food portion.
Each of these requirements had to be designed and built from what was available in a kitchen in New Jersey.
That she produced a working device from these constraints speaks to both her mechanical intelligence and her specific knowledge of exactly what the device needed to accomplish. She was not experimenting with design options; she knew what the patient needed and was figuring out how to build it.