험프리는 특허 냈습니다. (US patent NO. 4,873,909 )

요약은 너무 난해하고요. 링크 찾아가보면, 원본 pdf볼 수 있어요. 그림도 있네요.
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Stringed musical instrument

Abstract
A stringed musical instrument, in particular a guitar, including a body with a soundboard having an upper portion, and a neck having one end connected to the upper portion of the soundboard so that a portion of the neck extends over the soundboard to a distal second end, the soundboard and neck are connected so as to form an obtuse angle therebetween so that a fingerboard located on the upper surface of the neck has an elevation from the soundboard which increases in the direction of the distal second end of the neck.

전문: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=/netahtml/search-adv.htm&r=2&p=1&f=G&l=50&d=pall&S1=humphrey-thomas.INZZ.&OS=in/humphrey-thomas&RS=IN/humphrey-thomas