According to Asimov, two Scottish researchers have developed a "telechronic battery", which uses a series of 77,000 interconnected endochronometers to allow a final sample of thiotimoline to dissolve up to a day before water is added to an initial sample. Asimov says there is "strong, if indirect, evidence that the Soviet Union possesses even more sophisticated devices and is turning them out in commercial quantities". He believes that the Soviets are using telechronic batteries to determine ahead of time whether satellite launches will be successful.