Rev 8:1

1 When he opened the seventh seal, there followed a silence in heaven for about half an hour.

there was silence in heaven for about half an hour – there is a period of quietness, that follows the deaths of the Reformation wars, that ended with the Peace of Westphalia in 1648, until the outpouring of the holy spirit in 1917. This is approximately 267 years, or 1/2 hour of the clock of human history of 6,000 years. From the end of the cry of the Martyrs, “how long?” in Rev 6:10, until this next major event is a “half an hour.”