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.
127 days Until Winter 2016. The first day of winter is known as the winter solstice. It is the shortest day and the longest night of the year. Days Until: Christmas Eve Christmas New Years Eve New Years Day MLK Day Groundhog Day Valentines Day Presidents Day Easter.