I have had two instances when I could not see. One was in the night when I rolled over to see what time it was. My clock was always brightly lit, but that night I couldn't see a thing. I panicked and woke my husband by screaming, "I can't see!" He sat up and said, "Oh, go back to sleep. The electricity is off."
The other time, I was walking from the post office to our office. I always noticed when I got to where I could see the bank clock. That time, where I usually could see it, I couldn't. When I moved closer, I still couldn't! My heart started racing. I was scared silly. When I got as close as possible, I saw that the clock wasn't even there. It had been removed for repairs.