Density and Convection<span> at the Beach. </span>Convection<span> is heat transfer due to a density differential within a </span>fluid<span>. ... The </span>current<span> begins when the air over the hot sand is heated and begins to </span>rise<span> because of its lowered density. Air from above the ocean is colder and more dense.</span>
Led by the pigs, especially Napoleon and Snowball, the animals meet secretly for three months and learn the new system of thought called Animalism. Boxer and Clover, the two horses, help to convince the other animals.
