ScienceIQ.com

Silent Earthquakes

Try this demonstration of earthquake movement. Shape modeling clay into two blocks or get two firm sponge blocks. Press the sides of the blocks together while trying to slide them slowly past each other. You may notice that they stick at first, then suddenly slide. This is much like what happens when earth's plates (large sections of earth's solid ...

Continue reading...

SilentEarthquakes
Physics

Many Happy Returns!

The boomerang is a bent or angular throwing club with the characteristics of a multi-winged airfoil. When properly launched, the boomerang returns to the thrower. Although the boomerang is often ... Continue reading

ManyHappyReturns
Mathematics

Unit Of Luminous Intensity (candela)

Originally, each country had its own, and rather poorly reproducible, unit of luminous intensity; it was necessary to wait until 1909 to see a beginning of unification on the international level, when ... Continue reading

Candela
Biology

Why Are Zebra Mussels Successful As Invaders?

The zebra mussel (Dreissena polymorpha) is a small, non-native mussel originally found in Russia. In 1988, this animal was transported to North America in the ballast water of a transatlantic ... Continue reading

ZebraMusselsInvaders
Engineering

Sundials, Ancient Clocks

The earliest and simplest form of sundial is the shadow stick. The time of day is judged by the length and position of the stick's shadow. Some nomadic peoples still use this method for timekeeping. ... Continue reading

SundialsAncientClocks

Tea Time!

TeaTimeDid you know that a disease of coffee plantations made the British tea drinkers? In the 1700s Britain had many coffeehouses that served as popular social gathering places to discuss current events and conduct business. For example, the famous insurance company 'Lloyds of London' was started by patrons of Edward Lloyd's coffeehouse about 1774. These coffeehouses obtained their coffee from plantations in Ceylon (now known as Sri Lanka), the leading coffee exporter of the time. About 1870 a serious disease, coffee rust, struck these plantations and in 10 years had destroyed half of the coffee production. As a result of this disease former coffee plantations were replanted with more than a half-billion tea bushes.

A pound of tea yields 10 times as many cups of the brew as a pound of coffee, making tea much less expensive than coffee and allowing the lower classes to enjoy a stimulating beverage. So tea became a great leveler of British society.

Although rust-resistant coffee varieties have been developed, races of rust occur that overcome this resistance, and the disease continues to be a problem. Strict quarantines are enforced in coffee growing regions of the world, especially in Central America, in an attempt to prevent the establishment of rust in their coffee plantations.