Christopher Knight and Alan Butler further develop the work of Smyth's and Stecchini's "Grand Scheme" in their Civilization One hypothesis, which describes a megalithic system of units.[6] This system is claimed to be the source of all standard units used by civilization, and is so named after the Neolithic builders of megaliths. Knight and Butler contend the reconstructed megalithic yard (0.82966m) is a fundamental part of a megalithic system. Although the megalithic yard is the work of Alexander Thom, Knight and Butler make a novel contribution by speculating on how the MY may have been created by using a pendulum calibrated by observing Venus.