Here’s how to build a pendulum-controlled clock which can be made really accurate. Retro? – yes, but an interesting project all the same. You’ll need a spare quartz clock which must be adapted by ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. After decades of experiments with the ...

THE most accurate timekeepers of to - day are divided into two classes, depending on whether the restoring force of the oscillator is gravity, as in pendulum clocks, or elasticity, as in quartz ...