Earlier than reviewing the Montograph KF Spirograph Sport, let's deepen the topic of marine chronometers. Two essential options assist preserve the accuracy of marine chronometers. To start with, it's their use of giant pendulums. These pendulums are each heavier and bulkier, in comparison with what we usually see in wristwatches. The massive adjustable weights on the steadiness wheel rim additional enhance the second of inertia. The longer the second of inertia of a pendulum is, the extra its oscillations are steady. Small shocks or dents won’t intrude as a lot as if the second of inertia was much less. Second, the pendulums we see on marine chronometers are normally divided into incomplete and full circles. One of these steadiness is named the clearing steadiness. The compensation scale is a metal and brass sandwich whose diameter adjustments relying on the temperature to compensate for temperature-induced elasticity variations of the metal spirals used at the moment. Because the temperature will increase, a watch with an atypical metal hairspring will are inclined to waste time; the outer arms of a compensation scale transfer inward with the rise in temperature, which tends to trigger a time saving, "offsetting" the change in elasticity of the steadiness. Such balances have been present in marine chronometers, but in addition in high-quality pocket watches, as much as the invention of recent Nivarox-type alloys within the 1920s.