Abstract: A sample tube for the use in a nuclear magnetic apparatus comprising a sample tube, said sample tube being formed of a glass substance, wherein the magnetic susceptibility of said glass substance has been adjusted by incorporating therein a sufficient amount of one or more paramagnetic and/or diamagnetic substances so as to impart to said sample tube a magnetic susceptibility proximate to that of a liquid sample to be tested.

Abstract: The method for manufacturing a sample tube for the use in a nuclear magnetic resonance apparatus comprising the steps of: inserting a core bar into a tubular body made of glass or quartz, the core bar having a stepped portion and a remaining portion, the portion of the core bar with the stepped portion corresponding to a sample receiving chamber being larger in diameter than the remaining portion; gradually inserting the tubular body into an electric furnace for heating while allowing suction from a vacuum pump to act on the interior of the tubular body, thereby the whole tubular body being intimately attached for shaping to and along an outer peripheral surface of the core bar; withdrawing the core bar outside from a lower end opening of the tubular body; sealing by heating the lower end opening of the tubular body to form a bottom of the tube; and grinding the peripheral surface so that the whole tubular body will be equal in outer diameter.