On May 19, 1780 the skies grew dark at midday in New England. There had been reports of smoky skies for a few days already, but then it became so dark that animals returned to their sleeping quarters.
It was darkest in northeastern Massachusetts, southern New Hampshire and southwestern Maine, but it got dusky through most of New England and as far away as New York. At Morristown, New Jersey, Gen. George Washington noted it in his diary.
In the darkest area, people had to take their midday meals by candlelight. A Massachusetts resident noted, "In some places, the darkness was so great that persons could not see to read common print in the open air." In New Hampshire, wrote one person, "A sheet of white paper held within a few inches of the eyes was equally invisible with the blackest velvet."
At Hartford, Col. Abraham Davenport opposed adjourning the Connecticut legislature, thus: "The day of judgment is either approaching, or it is not. If it is not, there is no cause of an adjournment; if it is, I choose to be found doing my duty."
The source of the blackout was a mystery, although there was always speculation that it came from a faraway forest fire. The definitive answer came only in 2007. Read the entire story at Wired. http://www.wired.com/science/discoveries/news/2008/05/dayintech_0519
(image source: The Weather Doctor)