True blue: Jeans' color doesn't go deep

Q. Vast riches would come to anyone paid a royalty of a penny for every pair of blue jeans sold in the world. But the riches would disappear if these pants were truly sold as "blue" jeans instead of the "half-blue" or "quarter-blue" jeans that they are. Know the story here? ­L. Strauss

 A. The partly blue happens because real denim has blue warp yarns interwoven with white filling, and the dyed threads are only blue on the surface where the color penetrates, says Iowa State University textiles and clothing expert Grace Kunz. Yet the twill weave allows the blue yarns to be more exposed on the outside of the garment.

If the filling yarns were also dyed, the garment would feel scratchier and less comfortable, and more importantly, your legs and underwear would become decidedly blue from color transfer, at least until after several washings, she says. The surface-only blue dye explains why wear to the knees and seat mutes the color, as will commercial sand papering by hand or sand blasting for fashion styling.

Enough of this will shift the garment from blue to light blue to white, toning down brightness, subtling the appearance, and helping make "blue" jeans the hit they are worldwide. For a true hit on the wilder side, adding to pre-washed, sand-washed, acid-washed, stone-washed, etc., notes Ohio State University consumer and textile scientist Charles Noel, one manufacturer years ago offered a "distressed" version, done by shipping the jeans to Tennessee where the "finisher" spread them on the ground and riddled them with buckshot. Holey smokes!

Q. When it is noon in New York City, Winnipeg, Amsterdam, or Greenwich, what time is it at the North Pole? ­S. Claus

 A. It can be any time you want! The concept of time zones, which are based on longitude, falls apart at the poles, where all longitudinal lines intersect, says New Mexico Institute of Mining and Technology geophysicist Rick Aster. Here the sun simply spirals around the sky, moving from 23.5 degrees below the horizon at the winter solstice to 23.5 degrees above in mid-summer.

Local noon for anywhere is defined as when the sun is at its maximum elevation, adds University of Alaska- Fairbanks geophysicist Paul Layer. At the poles, the sun does not rise in the morning and set in the evening but is at approximately a constant elevation for all of a 24-hour day. "Exactly at the North Pole, sunrise is on the Spring equinox and sunset on the Fall equinox: So a year and a 'day' are the same thing!" Layer notes.

Scientists doing work at the South Pole (little happens at the North Pole), say Aster and Layer, need to synchronize their clocks to an agreed-upon time zone, possibly based on clocks of the nation of origin or maybe Coordinated Universal Time (UTC), which is the standard time at the prime (Greenwich) meridian at 0 degrees longitude.

Q. For males, tall is always "in." Are taller men more likely to win a mate and have kids? Is this why each new generation seems to be getting taller? ­S. O'Neal

A. Yes to the first question, says Daniel Nettle, lecturer in biological psychology at the Open University in Milton Keynes, England. The average height for men in Britain at the moment is 5'10", but the optimum height in terms of marriage success is 6'. For women, it's the other way around. The average height is 5'4", but the optimum height in terms of finding a husband is more like 5'1" or 5'2".

These two forces– the taller man advantage and the shorter woman advantage– roughly balance out, so there is probably no genetic change from generation to generation. "The increase in stature we see is instead the result of improved nutrition and reductions in infectious disease," Nettle says.

Send strange questions to brothers Bill and Rich at