Leg swelling related to fluid buildup. Leg swelling caused by the retention of fluid in leg tissues is known as peripheral edema. It can be caused by a problem with the circulatory system, the lymphatic system or the kidneys. Leg swelling isn't always a sign of a heart or circulation problem. You may often experience swelling due to fluid buildup from being overweight, being inactive, after sitting or standing for a long time, or wearing tight stockings. Factors related to fluid buildup include: Acute kidney failure.
Lois Lowry wrote Number the Stars along with many other books.
Hipparchus, a Greek astronomer who lived in the second century BC, is usually credited with formulating a system to classify the brightness of stars. He called the brightest star in each constellation first magnitude. Ptolemy, in 140 AD, refined Hipparchus' system and used a 1 to 6 scale to compare star brightness, with 1 being the brightest and 6 the faintest.