Q: As all too many in the world know all too well, a hurricane can be a fearsome thing. How much power does one have, and where does it come from?
A: Hurricanes are among the most powerful of Earthly phenomena, unloosing some 1,000,000,000,000,000 Watts, 3,000 times the total electrical power generated in the world, say physicists Andrew Gavrin and Gregor Novak of Indiana University-Purdue University-Indianapolis. This is equivalent to exploding 500,000 Hiroshima-type atomic bombs per day. The fundamental source of this power is the condensation of water. Think how much heat energy it takes to boil off a kettle of water, about 2,250,000 joules of energy for a kilogram. The reverse of this happens in a storm, where the water is condensed instead of evaporated, making available a huge quantity of energy.
The necessary ingredients for a hurricane are a large area of warm ocean water, which provides the energy, and other factors that get the storm organized and going. Condensing moisture in a low-pressure region releases energy, heating the air, which rises and pulls in more air from around the outside toward the center. Now add in the Coriolis force from the spinning Earth, and a whale of a whirl ensues. A hurricane can continue for many days over open water, but over land the lack of moisture and increased friction will slow it–though often not before much human grief has been delivered.
Q: How common are Siamese twins such as the “Biddenden Maids” of England, depicted as joined separately at both the hips and shoulders? Tradition has it that when 34-year-old Mary died, Eliza refused any attempt at separation from her sister’s corpse, saying “As we came together we will also go together.” She died several hours later.
A: They are often cited in the medical literature as one of the earliest cases of conjoined twins on record, though reports vary on their birth year (1100? 1500?) and other details, says Dr. Jan Bondeson in “The Two-Headed Boy and Other Medical Marvels.” The popular Biddenden cakes at festivals of the 18th century clearly depicted them joined at the hips and shoulders, with a large open space in between.
Conjoined twins occur approximately once in every 100,000 deliveries, with some 60% stillborn. The most common type is joined at the chest, then upper abdomen, pelvis, sacrum and skull. What is rare is for the twins to have two separate sites of conjunction, and usually only if close together, as thorax and abdomen. “Very few modern teratologists accept the possibility of a fusion at the hips and shoulders, particularly in a pair of viable twins.”
Authorities now believe Mary and Eliza were joined only at the hips (8% of cases), says Bondeson. To walk, they probably put their arms around each other’s shoulders, making it appear as if joined at the shoulders. First successful surgical separation of such twins was in 1950.