New England’s Dark Day refers to an event that occurred on May 19, 1780, when an unusual darkening of the day sky was observed over the New England states and parts of Canada. The primary cause of the event is believed to have been a combination of smoke from forest fires, a thick fog and cloud cover. The darkness was so complete that candles were required from noon on. It did not disperse until the middle of the next night. For several days before the Dark Day, the sun as viewed from New England appeared to be red, and the sky appeared yellow. While the darkness was present, soot was observed to be collected in rivers and in rain water, suggesting the presence of smoke. Also, when the night really came in, observers saw the moon colored red. Today, some people, especially those among Seventh-day Adventists citing extracts of Biblically sequential events, “[...] the sun shall be darkened and the moon shall not give her light [...]” (Matthew 24:29) are signs preceding the return of Christ and interpretations of the event as cited by Ellen G. White, believe that the Dark Day was a fulfillment of Biblical and end-times prophecy.

(In: http://listverse.com/2011/01/17/10-curious-tales-or-oddities-from-history.)