Abstract: A throwaway thermometer structure (10,110) comprising essentially a synthetic resin wall member (13,113) having a thin gas impermeable layer (11,111) defining the inner capillary bore (12,112) thereof. The outer wall member effectively defines a jacket and the inner layer effectively defines a core tube. Interlock structure (20,120) is provided for effectively accurately maintaining the longitudinal disposition of the jacket and core tube. Such maintained disposition provides effective accurate maintained disposition of a scale (17) or the like, provided on the jacket portion of the thermometer. In one form, the interlock (20) may be directly between the jacket and the core tube. In an alternate form, the interlock (120) is indirectly between the jacket and core tube, being effectively provided between the reservoir bulb (114) and the core tube (111), with the reservoir bulb being fixedly secured to the jacket.

Abstract: A disposable throwaway thermometer formed of synthetic resin having a gas impervious layer effectively maintaining a preselected vacuum condition within the completed thermometer. The impervious layer may be provided as a glass core tube defining the capillary bore of the thermometer. The glass layer may have a thickness of substantially less than that of the synthetic resin layer. One end of the glass core tube may be provided with a bulb element defining the reservoir chamber of the thermometer. The other end of the glass core tube may be sealingly closed as by fusion. The composite glass core and synthetic resin jacket may be formed by molding of the synthetic resin is situ about the glass core. The reservoir bulb may be sealingly secured to one end of the glass core tube.