A blood blister forms when skin and small blood vessels are damaged without breaking the skin. Trapped beneath the skin surface is some blood and skin fluid. Blood blisters are commonly caused by accidents in which the skin is pinched by a tool or a heavy weight, or they may occur from constant rubbing back and forth.
1 Sunshine hours in Chicago, Illinois range between 3:42 per day in December & 10:14 for each day in July. 2  The longest day of the year is 15:02 long and the shortest day is 8:57 long.  The longest day is 6:04 longer than the shortest day.
Did you ever wonder why the days are so long in the summer and so short in the winter? The length changes throughout the year. In the summer, around June 20 or 21, we experience the summer solstice, which is the longest day of the year. And in the winter, December 21 or 22 is the winter solstice, or shortest day. But wait! If you live in Australia, you experience the oppositeâthe longest day is in December and the shortest is in June.