Writer & Geek

By Ep.Log MediaSociety & Culture Documentary Science Technology History

Writer & Geek episodes

May 20, 2018 044: Bizarre History Of Birth Control
Doing it isn't just for having kids, so how did people prevent that through history?
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40 min
May 13, 2018 043 - Beer Talk: Why learn history?
Why learning history is important
In this episode, we talk about the importance of history and why we should learn. We also take a look at how history is taught and why there is a need to reform it with the use of current technologies.
Thomas Ketchell’s talk
24 min
May 13, 2018 043: Beer Talk: Why Learn History?
Is history important? Why should we learn it?
See omnystudio.com/listener for privacy information.
24 min
May 06, 2018042 - History of Timekeeping
Definition of time
A second

The duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of ground state of the Cesium 133 atom.
That’s lovely, but what does it mean? Hang on tight, we’ll come to that. But before that, let’s go back in history, few thousand years. To the land of mighty Egyptians. Yeah, you just thought of Pyramids and the movie Mummy, didn’t you? Yeah, moving along!
Sun to the rescue
Timekeeping became a necessity when humans started being social. As with everything on earth, it all started with Sun. Being the source of a vast amount of energy in the form of light, what better way of tracking time than to use that light.
Egyptians - the timemasters
Obelisks: An Egyptian invention. Shadows are tracked to calculate the time of day.

Sundial: A device that uses shadow cast by sunlight to measure time as the sun moves overhead. Egyptians used these in B.C. 3500. In 1500 B.C. Egyptians built a more accurate sundial which was divided into 10 parts. This one was accurate only half the time and afternoon it had to be rotated by 180°

Issues:
Path of sun changes throughout the year.

Doesn’t work on rainy or overcast days.

Doesn’t work during the night.

Water Clocks: Used mostly as time measuring devices.
Mechanical Clocks
First mechanical clocks might have been used in monasteries to keep monks aware of the prayer times.

Most of these were large weight driven “turret” clocks which stuck at every hour and did not have a face or a hand.

Salisbury Cathedral in England has the oldest clock which chimes every hour. These type of clocks had errors of up to half an hour a day and weren’t accurate.

During mid of the 1400s, German and Italian clockmakers started making clocks that made use of wound spring. Most of these had only hour hands and the minute hand came into existence only during the 1650s.
Pendulums
Master inventor Galileo devised the timekeeping property of pendulum and in 1656, Christiaan Huygens started using the pendulum as a time controller in clocks.

The time period of a pendulum was independent of the mass of the pendulum and to the extent of the swing, but depended only on the length of the pendulum. A pendulum of around 99 cm (39 inches) has a time period of around 1 sec. Even an increase in length by 0.025 mm would make a difference of 1 sec in a day. Which means a steel pendulum can lose up to a second a day with a temperature variation of 2.2°C. A special alloy called “Invar” which has a small co-efficient of expansion is sometimes used to make pendulums.

A series of clocks which were weight driven and had pendulums were devised and built. Due to their weight they were not suitable for hanging from the wall, instead, the casing was extended towards the ground and this led to the creation of “Grandfather” clocks.

In 1670 the seconds pendulum was added to the clock which oscillated once every second.

An escape wheel is used which is allowed to rotate one tooth per double swing of the pendulum and also transmits the impulse to the pendulum.

Escapement has two main functions: transmit the impulse without hampering the free swing and to transmit a uniform impulse.

Edmund Beckett invented a gravity clock using double three-legged gravity escapement and used this for Westminster which we adorably call The Big Ben :wink:.
The Components
Escapement: Escapement is used to transfer the gravitational force acting on the weights to the clock’s mechanism. In this mechanism, a weight unwinds a rope from a barrel which turns the toothed escape wheel. A vertical rod with pellets at each end called a verge is used. When the weight drops and the wheel rotates, the top pallet arrests the wheel resulting in oscillation on the regulating weights. This oscillation turns the verge and that releases the wheel from the pellet until it is caught by the second pellet on the other side of the verge. This process is repeated. This action produces the “tick-tock”.

The wheelwork: This mechanism, also called the train is responsible for transmitting the motion from the weight or spring mechanism to the hands of the clock through a series of wheels and pinions precisely calibrated to ensure steady transmission of power. There is a gearing mechanism that drives the clock and uses a 12:1 gearing ratio to move the hour hand.
Electric Clocks
First made in 1840, the first electric clock had a pendulum and spring mechanism and used an electrical impulse to operate a number of dials.

The first complete electric clock was invented in 1906.
Quart crystals
Quartz crystal was first used in clocks in 1929. A big leap in precise timekeeping.

A ring of quartz of 2.5 mm in diameter is suspended by threads in a heat-resistant chamber. Electrodes are connected to the surface of the ring and the 100,000 hertz frequency of vibration is reduced by a process called frequency division and applied to a synchronous motor.

6 million to 1 ratio of gearing is used to move the second hand and the precision is of the order of one second every 10 years.
Watches
Watches came into use around the 1500s. Peter Henlein, a locksmith from Germany made early models of watches using verge as the escapement method.

Germany and France produced early watches which were not wrist watches but were worn on chains around the neck.

These early watches had no minute or second hands and had only hour hands.

Early watches used wound up springs, which were coil springs that could be wound up to store energy. This energy is then transferred using wheel train and escapement.

The major drawback was the change in torque as the spring unwinds. This was countered by use of fusee, a cone-shaped, grooved pulley system that kept the torque constant by the variable diameter of the cone.
Navigation and need for precision
Navigators needed to have accurate ways of determining the time to also determine their location.
Latitude could be calculated based on the position of sun’s angle at noon.

Time at a reference point was necessary to identify the longitude. At equator 15° change in latitude is equivalent to an hours difference in time.

Pendulums do not work well at sea.

In 1714, the Engish government promised a reward of £20,000 to anyone who can measure longitude to the accuracy of 0.5° which corresponds to an error of 35 miles at the equator and an accuracy of 3 s/day.

The prize was won by John Harrison who made the sea going H4 clocks with the accuracy of 0.2 s/day with the error of only 30 km on a 7-day trip.
Greenwich Mean Time
Set as a standard in 1884.

Since the path of the sun varies, there was a deviation of +/- 15 mins. Hence mean annual average of motion of sun was considered.

1 second = 1/864,000 of a mean day.

Issues:
Variation in earth’s rotation.

Weather

Tides

Replaced by UTC (Coordinated Universal Time) which is pretty much similar to GMT and is maintained by an ensemble of around 260 clocks maintained in 40 countries.
Atomic clocks
Atomic clocks were a major breakthrough in the development of highly accurate clocks for use in various scientific devices and in modern exploration including space.
1955: Cesium atomic clock was invented by Essen and Parry at National Physical Laboratory.

More clocks were reproduced in the following years and Caesium clocks were adopted as the basis for time measurement.

Present day atomic clocks have an accuracy of 1 sec in 3 billion years.
Working of atomic clock
Uses quantum mechanical states of energy and precise energy levels of electrons.

The frequency at which Cesium releases peak energy is calculated and time is calculated accordingly.

High precision. Used in space technology where nanosecond level of precision is required.
Awesome podcasts hosted by our friends that can help with productivity!
The Passion People Project

The Inspiring Talk
Image: Shankar’s Instagram
55 min
May 06, 2018 042: History Of Timekeeping
Clocks and watches are devine! We talk about how humans felt need for timekeeping and all about it.
See omnystudio.com/listener for privacy information.
55 min
April 29, 2018 041: Coffee Rules The World
Coffee is the beverage of champions. We talk about how coffee is extracted and other stuff related to coffee.
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48 min
April 29, 2018041 - Coffee rules the world
World runs on coffee
Coffee is one of the most popular beverages on the planet alongside water and tea. It is the second most traded commodity after oil. Coffee has also given rise to a culture of coffee shops or coffee houses which seems to be a recent phenomenon. But are they really a thing of 21st century or do they have some history? Let’s find out.
Beverage of choice
Coffee is a magical drink of choice. Its ever-increasing popularity can be attributed to its versatility and of course Caffeine the magic alkaloid that gives you bliss as you sip your coffee down.
The coffee plant originated in Africa

Two different variety of Coffee:
Arabica: The more popular and expensive variety, this is considered to be milder and more flavourful. The bean is flatter and elongated and requires a cool sub-tropical climate. Typically grows around the elevation ranging from 2000 - 6500 ft where it needs sun, moisture and shade. Largest producers of Arabica are Latin America, Asia, Arabia and East Africa.

Robusta: This is cheaper to produce but has almost twice the quantity of caffeine than the Arabica coffee. Robusta beans are rounder and can grow at lower altitudes (sea level - 2000 ft.). Central and Western Africa, South East Asia and Brazil are the leading producers of Robusta.

History of Coffee
Coffee plants grew in the wild in the area called Kefa or Kaffa in Ethiopia. These plants were taken to Arabia and cultivated around the 15th century.

Legend is attributed to a goatherd by the name Kaldi who noticed that his heard started behaving weirdly after eating certain berries. He tasted them and felt ecstatic as well. He made coffee popular according to the legend.

Since it was an intoxicating drink, Islam forbade drinking coffee since such drinks are prohibited by Quran.

Despite the risk, coffee lovers grew in leaps and bounds within Arabia and drink became popular.

This paved way for the creation of “Coffeehouses” called Qahveh Khanehs and gave rise to the coffee house culture. They first appeared in Mecca around the 15th century and were popular places to catch up with friends.

Coffee came to Europe around 16th and 17th centuries and spread across Europe.

Some countries prohibited coffee stating they are magical potions.

Coffee houses became popular in Britain and British colonies by 17th century.

Yemen was almost the only supplier of coffee until the close of 17th century. But the popularity of the beverage took it all the way to Java in Indonesia and Americas along with Hawaii (since 1825).

By 20th century Brazil became a leading producer and exporter of Coffee.

In 19th and 20th centuries, coffee machines came into existence and various new methods of producing coffee came into being.

Instant coffee came into popularity and production was perfected post-1950 leading to the increased production of Robusta.
Caffeine - the magical ingredient
Caffeine is an alkaloid which is present in coffee, tea, cocoa and in some other nuts and berries.

It normally is a white powder highly soluble in hot water.

Caffeine stimulates central nervous system, heart and kidneys. It is also a mild diuretic (removes urine).

Used as an antidote to respiratory depression caused by overdose.

Negative effects: Insomnia, anxiety, irritation etc.

Positive effects: Increased alertness and improved motor performance.

Decaffeinated coffee became popular to control the amount of coffee in the system.
Production of coffee
Coffee cherries contain coffee beans, usually two. Single beaned berries are called pea beans and are said to be sweeter and flavourful.

Beans are separated from the berries and the dried to reduce the moisture content from 65-70% down to 12-13%.

Three techniques are used for processing coffee:
Dry method: In this process, the berries are placed under the sun on concrete or brick patios. This is the simplest way of processing and is least expensive. Practised in areas with dry and warm climate like Ethiopia and Brazil. The berries are raked to move them around and to prevent fermentation. The process takes few days to around four weeks. Overdrying breaks the coffee and underlying causes fungi and other bacteria attack. Once dried, the coffee beans are separated by machinery.

Wet method: This method produces better quality coffee and requires much more sophisticated equipment than the dry method. The skin and the pulp are removed using a pulping machine that uses a rotating drum. The thin layer of pulp that still remains is removed by fermentation that happens over three days as the wet seeds are kept in tanks. Remaining pulp is washed off and the beans are dried under the sun or by passing hot air.

Pulped natural process: In this third way of processing, the pulp is removed mechanically but there is no intermediate fermentation and the remaining pulp is removed once the beans dry off. This is a combination of dry and wet techniques. The beans produced in this method are both sweet and acidic.

Post the processing the coffee is graded and stored.
Roasting and Grinding
Coffee beans are roasted between 180-250 °C from 7-20 mins releasing carbon dioxide, carbon monoxide and water.

The beans lose weight and expand under the roasting process.

Roasting gives the aroma to the coffee.

Overroasting kills the flavour which is done in the case of Robusta beans to remove the strong coffee flavour.

The old method was to roast coffee beans in a rotating metal cylinder above a source of heat. Modern method uses hot air to roast the beans. Rotation ensures even roasting.

Grinding is either done before packaging or done by the consumer depending on the brew method involved. We use a French Press, hence coarsely ground coffee is what purchase.
Packaging and Brewing
Coffee needs to be sealed airtight to prevent moisture from reaching it.

Modern methods use inert gas and aluminium or polyethene compounds.

Different methods of brewing:
French Press

Pour over

Moka Pot

Aeropress

Cold brewing

Espresso

Instant coffee is a soluble coffee concentrate which does not need to be brewed but the flavour is usually inferior to brewed coffee.

Kopi Luwak (Civet coffee).
Decaf
For people who do not tolerate caffeine, it is removed from the coffee using chemical solvents, carbon filtering or carbon dioxide extraction. Caffeine is extracted just before roasting.

The chemical agent is either used to treat the beans directly or the water-based solution in which the beans are soaked.

Swiss water process is used to get more flavourful beans. The first batch of beans are processed in hot water and that water is used for washing the next bath of the beans.

100% decaf is not a possibility.
Our favourite coffee makers/shops
Please note that this is not an endorsement, we just love their coffee that we want everyone to know about them :wink:.
Coffee Mechanics

The Roastery

Third Wave Roasters

Blue Tokai

Flying Squirrel
Sources
Kickass Facts

ListVerse
Image: Vishnu’s 500px
48 min
April 15, 2018 040: Serial Killer Files Part 4 - DC Sniper
We talk about the DC Snipers who terrorized the US in 2002.
See omnystudio.com/listener for privacy information.
45 min
April 15, 2018040 - Serial Killer Files Part 4: DC Sniper
The DC Sniper was a series of coordinated shooting on civilians at random during October 2002 which were perpetrated by John Allen Muhammad and Lee Boyd Malvo.
Duration:
Preliminary shooting: 16 February 2002 - 26 September 2002

Sniper shooting: 02 October 2002 - 24 October 2002

Perpetrators: John Allen Muhammad and Lee Boyd Malvo

Casualty: 17 deaths and 10 injuries

Location: Arizona, Maryland, Virginia, and Washington, D.C.

Motive: Anger, Greed, Revenge

Date apprehended: 24 October 2002
Timeline:
Preliminary shooting:
16 February 2002: 21-year-old Keenya Cook shot and killed at Tacoma, Washington. She was the niece of John Allen’s ex-wife’s friend who supported her decision to divorce.

19 March 2002: 60-year-old Jerry Taylor shot and killed while playing golf at Tucson, Arizona.

01 August 2002: 51-year-old John Gaeta shot while changing tires at a parking lot in Hammond, Louisiana. He survives.

05 September 2002: 55-year-old Paul LaRuffa, a pizzeria owner in Clinton, Maryland, shot 6 times but survives.

21 September 2002: 41-year-old Million A. Woldemariam shot dead in Atlanta, Georgia. 52-year-old Claudine Parker, a liquor store clerk, shot dead in Montgomery, Alabama. The killings happen in the span of nineteen hours.

23 September 2002: 45-year-old Hong Im Ballenger shot death in Baton Rouge, Louisiana with a Bushmaster rifle.
Sniper Shooting:
Location: Montgomery County, Maryland
02 October 2002: A shot 55-year-old through a window of a Michaels craft store in Aspen Hill. No one hurt. One hour later,55 year-old James Martin shot dead at a parking lot in Wheaton.

03 October 2002:
39-year-old James L. Buchanan shot dead at 11411 Rockville Pike near Rockville, Maryland, while mowing grass.

54-year-old part-time taxi driver, Prem Kumar Walekar shot dead at Aspen Hill while pumping gas.

34-year-old babysitter and housekeeper Sarah Ramos killed at 3701 Rossmoor Boulevard at the Leisure World Shopping Center in Norbeck, while seated on a bench reading a book.

25-year-old Lori Ann Lewis-Rivera shot dead while vacuuming her Dodge Caravan at the intersection of Connecticut and Knowles Avenues.

72-year-old Pascal Charlot shot dead while walking on Georgia Avenue at Kalmia Road.

All the killing except Pascal Charlot happened in the morning between a space of two hours of time.
Location: Virginia and other areas
04 October 2002: 43-year-old homemaker Caroline Seawell shot and wounded at Spotsylvania Mall in Spotsylvania.

07 October 2002: 13-year-old Iran Brown shot and injured as he arrived at the Benjamin Tasker Middle School at 4901 Collington Road in Bowie, Maryland.

09 October 2002: 53-year-old Dean Harold Meyers shot dead while pumping gas at 7203 Sudley Road in Prince William County, Virginia.

11 October 2002: 53-year-old businessman Kenneth Bridges shot dead at Exxon station off Interstate 95 in Spotsylvania County, Virginia.

14 October 2002: 47-year-old Linda Franklin, an FBI intelligence analyst 35-year-old shot dead - in a covered parking lot at Home Depot in Fairfax County, Virginia.

19 October 2002: 37-year-old Jeffrey Hopper shot at State Route 54 in Ashland, Virginia. He survives.

22 October 2002: 35 year old bus driver Conrad Johnson, shot dead at the 14100 block of Grand Pre Road in Aspen Hill.
Audio:
Passing Over Freestock Audio

Footsteps Soundible

Sniper Rifle Soundible
Image: pixabay
45 min
April 08, 2018 039: Why Do The Continents Move
Was the world different when dinosaurs lived? We discuss about plate techtonics in this episode
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22 min