Cool Fact of the Day
Laser Power Units
How did early laser researchers measure beam power?
In the earliest days of laser research, power of the beams was measured in milliwatts, hardly
enough energy to do any damage. But lasers increased in power until they were able to melt
holes in metal, at which point they were much more dangerous.
During that time, a laser researcher at Raytheon suggested a new measurement of laser
power: the Gillette. A beam's power in Gillettes was the number of blue razor blades the laser
could puncture in one burst. It was only an approximate measurement, but it gave a rough
idea of the beam's power.
Today, the most powerful lasers can instantly vaporize whole stacks of razor blades.
Super-powerful laser beams are being used as industrial metal cutters, weapons of war,
nuclear fusion ignition sources, and ground-based power sources for experimental spacecraft.
Hole drilling was one of the first practical uses for lasers:
industrial-lasers.com
Freqently Asked Questions about lasers, with answers:
misty.com
Femtosecond lasers make the cleanest cuts:
features.learningkingdom.com
Cool Word of the Day
pavilion [n. puh-VIL-yun]
A pavilion is a light building (sometimes a temporary one) for entertainment, recreation, or
sporting events, or an annex or wing of a larger building. A pavilion can also be a large tent,
especially an elaborate one that is set up for use at special events.
The word pavilion was inspired by the resemblance of a tent to a butterfly with outstretched
wings. It comes to us via Old French from the Latin papilio (butterfly).
Person of the Day
Samuel Johnson, 1709-84
English writer and lexicographer
Considered one of the literary giants of the 18th century, Samuel Johnson was educated at
Oxford University. Suffering from ill health since infancy, he endured a variety of medical
problems, including a "constitutional nervous derangement" that resulted in twitching and other
behaviors that set him apart from his fellow students.
Leaving the school prior to graduation because of financial difficulties, Johnson decided to
become a teacher but met with little success, due in part to his poor health. In 1737, he went
to London and began to write as an alternative to teaching. A satire, initially published
anonymously, was praised by noted poet Alexander Pope. That effort was followed by a
variety of poems, essays, and plays that met with critical acclaim.
In 1747, Johnson began a project commissioned by a group of booksellers. This work, the
"Dictionary of the English Language" appeared in 1755. Nine years later, he founded the
famed Literary Club, which included among its distinguished members historian Edward
Gibbon, economist Adam Smith, and statesman Edmund Burke.
More about Samuel Johnson:
andromeda.rutgers.edu
samueljohnson.com
Quotes of the Day
Understanding Human Instinct; On the nature and value of instinct:
"Nothing is so powerful as an insight into human nature... what compulsions drive a man, what
instincts dominate his action... if you know these things about a man you can touch him at the
core of his being."
-- William Bernbach, American advertising executive and copywriter
"There is only one way in the world to be distinguished. Follow your instinct! Be yourself, and
you'll be somebody. Be one more blind follower of the blind, and you will have the oblivion
you desire."
-- Bliss Carman, Canadian poet and author
"The very essence of instinct is that it's followed independently of reason."
-- Charles Darwin, English naturalist and author
"Instinct is the nose of the mind."
-- Delphine de Girardin, French novelist, poet
Today in History
May 10th
1773: East India Company Authorized to Export Tea
The British parliament authorized the East India Company to export half a million pounds of
tea to the American colonies without imposing the usual duties and tariffs. This measure, which
allowed the company to undersell other tea available in the colonies, saved it from
bankruptcy.
History of the East India Company:
theeastindiacompany.com
1849: Astor Place Riot
Fifteen thousand working-class men rioted outside the Astor Place Opera House to protest
the choice of Shakespearean actor; they viewed the Englishman William Charles Macready as
offensively elitist. The unarmed police were unable to handle or protect themselves against the
stone-throwing crowd, and the National Guard was called in as reinforcement. Armed with
guns they were able to disperse the mob, which sustained over 100 casualties, including at
least 22 deaths.
More about the riot:
mcny.org
1857: Indian Mutiny Started
In the mid-19th century, the British ruled India through the East India Company, which in turn
depended on the British Indian Army to exercise its power. Although it was commanded by
British soldiers, Indian soldiers, called "sepoys", constituted 96% of that army.
On May 10, 1857 Indian soldiers mutinied at the Meerut cantonment near Delhi, starting a
year-long uprising against the British. The mutiny was sparked by the introduction of rifle
cartridges rumored to have been greased with pig or cow fat, an offence to the religious
beliefs of both Muslim and Hindu sepoys.
In the course of the next year, the British, relying primarily on those Indian troops who
remained loyal, managed to reestablish control. The mutineers finally surrendered on June 20,
1858. The mutiny, also known as India's First War of Independence, had lasting effects on
the relationship between Britain and India.
A brief history of the Indian Mutiny:
kamat.com
An overview of the Mutiny's causes and consequences:
qub.ac.uk
1869: First Transcontinental Railroad Completed
The first transcontinental railroad was completed at Promontory Point, Utah. Officials from
the Union Pacific and Central Pacific lines celebrated by driving a golden spike into the last
rail. The four to six months that generally took pioneers to traverse the United Stated was
now reduced to six days.
The project owed its success to the efforts of four visionaries:
sfmuseum.org
1967: Jumper Became First Woman Chair in Seminole Council
Nurse, journalist, and writer Betty Mae Jumper became the first woman chair in the Seminole
Council in Florida, and the first woman to assume the position of "Chief" of a federally-
recognized tribe. In 1995, she was inducted into the Women's Hall of Fame of Florida.
1994: Nelson Mandela Inaugurated As President Of South Africa
Nelson Mandela dedicated his life to the struggle against apartheid, the official policy of racial
segregation formerly practiced in the Republic of South Africa. Because of his beliefs and his
activities on behalf of the outlawed African National Congress (ANC), the all-white South
African government imprisoned him for 25 years.
In 1990, the resistance campaign within South Africa along with international political and
economic pressure finally had their desired effect: President F. W. de Klerk ended the
government ban on the ANC and freed Mandela. Taking up the leadership of the ANC,
Mandela spent the next several years negotiating an end to apartheid and white minority rule.
The negotiations led to the nation's first all-race national elections in April 1994 and Nelson
Mandela's inauguration as the first black president of South Africa on May 10th. In his
inaugural speech he pledged himself to a policy of reconciliation and the rebuilding of South
Africa as "a rainbow nation at peace with itself and the world."
Text of Mandela's inauguration speech:
wsu.edu:8080/~wldciv/world_civ_reader/world_civ_reader_2/
mandela.html
More about Nelson Mandela:
anc.org.za
Holidays & Events
May 10
Commemoration of National Institutions, Cannes Film Festival
CAMEROON: COMMEMORATION OF NATIONAL INSTITUTIONS
The Republic of Cameroon on the western coast of Africa celebrates a national holiday today,
commemorating the date in 1957 when its Legislative Assembly met for the first time. French
Cameroon was set up as an autonomous state in 1957 and became an independent republic in
1960.
More about Cameroon:
west-africa.com
FRANCE: CANNES FILM FESTIVAL
Probably the most important event of the year for the film industry, This 54th annual Cannes
Film Festival lasts until May 20th. Films will compete for the prestigious Palme D'Or awards;
this year the jury will be presided over by Liv Ullman. The festival features glitter and glamour
as stars and directors hit the town to promote their films, view international premieres, and
make deals.
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