Among other things, an apparatus includes a combination of a fissionable material, a molten salt, and a moderator material including one or more hydrides, one or more deuterides, or a combination of two or more of them. A hydraulically actuated piston is withdrawn to form the desired cavities and then extended to implode the cavities. A pair of core pins, positioned within the mold cavity during the lens forming process, will produce a pair of haptic-mounting holes within the lens. A method entails fabricating the MEMS device and forming trenchesin the top surface of the structural layer of the MEMS device. The standard quotient defines a standard clock correction value.