In a mask for beam exposure, a membrane structure for endless patterns and a stencil structure for terminated patterns are provided in combination. When the container is secured to the dosing assembly, a recognition feature on the container is adapted to co-operate with a variable resistor disposed in the dosing assembly to thereby facilitate an identification of the specific type of container which is secured to the dosing assembly. As the sample is cooled, the beam reflections are detected and indicate the wax to crystallization temperature. The cable is received within the gripping sleeve, which is biased to engage and grip the cable along its length. The beams stay parallel to the ground but adopt any inclination in response to an electric screw drive operated from a hand held cable connected control. A fan provides a partial vacuum to the internal and external air intake ports.