How to make butter  Butter has been a part of the human pantry
for about a week short of the time we have been keeping cows.
When cow's milk (straight out of the udder, homogenization and
pasteurization are still centuries in the future) is left still,
the cream floats to the top. Cream consists principally of the
components of whole milk that have a lower specific gravity--
mostly, the fat. Milkfat in its natural state is contained in
"fat globules," which, exactly as they sound, are microscopic
lumps of fat suspended in a liquid composed mostly of water,
with a little protein mixed in.  The upshot of all this dry
chemistry is that if you take cream and agitate (or "whip") it
for a little while, you can break up some of these globules and
introduce air into the mixture. If you whip it more, you'll
break up more and make the cream stiffer. If you whip it even
more, you'll reach the point where the globules collect into
masses so heavy that they displace the air, collecting into a
solid mass. This solid mass is