Abstract: A boiler having an improved plastic closure having a plastic and/or plastic-glass joint for connecting laboratory ware made of a material having different thermal expansion. The plastic joint includes a tubular plastic section having a compression ring secured at its end which recesses the labware of lower thermal expansion. The plastic-glass joint further includes a shorter standard tapered glass joint.

Abstract: Improved metal coated glassware and other brittle, non-metallic engineering materials, including items for laboratory and industry, which items are ordinarily brittle and subject to breakage or rupture under relatively low pressures and relatively minor impacts, utilizing an anti-bonding film, such as graphite, between the external surface of the glass, and a metal coating, which is generally chemically vapor deposited. The coated products have good impact strength, shock resistance, good heat distribution, good pressure capability, and an extremely high safety factor. Brittle fracture or rupture is a fracture unaccompanied by plastic or permanent deformation. Brittleness is that quality or property of a material that leads to crack propagation without plastic deformation.