• Welcome to Tamil Brahmins forums.

    You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our Free Brahmin Community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

    If you have any problems with the registration process or your account login, please contact contact us.

Did you know that...?

Status
Not open for further replies.
[FONT=comic sans ms,sans-serif]Iron # 5.

Iron's worst enemy.

Rust and corrosion are the major serious threats for all iron structures. Greeks coated iron with a layer of Tin to prevent it from rusting-as early as Fifth Century B.C!

Ancient Indians knew the secret of making rust-proof-iron.Sun Palaces were constructed along the coast of Kanarek more than 1500 years ago. They remain in good shape despite the floods and the under water submersion.

The famous rust proof Asoka pillar defies the destructive forces of nature and baffles the scientists. India was famous for its steel goods in ancient time. The process employed in making the rust proof iron remains a secret to everyone including the Indians!

Stainless steel was the next logical development. Now transparent stainless steel has been discovered. Tiny pores are created between the crystalline structures by
electrochemical process rendering S.S transparent.

Modern steel makers can produce the right kind of steel for the right job. Some of the types of steel known today are Stainless Steel, Ball bearing steel, Spring Steel, Temperature resistant iron and Diamond Steel.

Tungsten is the hardest substance known-second only to diamond. By adding 5 percent Tungsten, extra strong diamond steel can be produced .

(To be continued...) [/FONT]
 
[FONT=comic sans ms,sans-serif]Iron #6.

Uses of Iron.

The demand for iron is large and 96 percent of iron produced is used in Industry, Agriculture and various modes of transportation. Modern Skyscrapers have iron skeleton to bear the weight of the building. Rail roads, boats, ships, cars and all types of vehicles need iron. Bombs and shells are made of iron in order to destroy the enemy tanks, also made of iron.

Iron can be used in gardening, cultivating land, building houses, and for transportation. It can also be used to fight, rob, kill, plunder and loot.

In the recent past many new rivals have emerged to the age old iron. Aluminum, Titanium, Vanadium, Beryllium, Zirconium are some of the new contenders for the coveted place held by iron. But iron still remains the foundation of metallurgy mechanical engineering, communication, transport, ships etc.

The model of an Iron crystal lattice was magnified 1,65,000 million times and a unique Atomium was constructed in the venue of the World's Industrial Fair, in Brussels, in 1958.

Atomium consisted of nine big metal spheres-each 18 meters in diameter. They looked as if they were suspended in mid air! Eight of these spheres occupied the apexes of a giant cube. The ninth was right in the middle.This symbolized the grandeur and greatness of Iron-the most indispensable metal in industry.

(The tale of Tin follows)
[/FONT]
 
[FONT=comic sans ms,sans-serif]Tin # 1.

The tale of Tin.

At the end of 19th Century, a train carrying bars of Tin was sent from Holland to Russia.When the train reached its destination, the rail cars contained a gray dust and the Tin bars were completely missing!

An expedition took care of everything needed for a trip to Siberia. But soon the spoons and bowls made of Tin crumbled into a gray dust and the team had to carve new ones out of wood!

In the beginning of the 20th Century, the Quartermaster of an army depot in St.Peters-burgh found that all the buttons had vanished from the uniforms of the soldiers. The box containing the spare buttons had a gray dust in it!

In order to prove his innocence and clear his name, he had the dust analyzed. The verdict...the dust was Tin no doubt but it had crumbled to form the useless gray dust since it had suffered from the 'Tin Plague!'

What caused the Tin Plague? Was there an effective treatment to this unusual plague?

In the middle ages witchcraft was believed to be the cause of the tin plague. Many perfectly harmless and innocent women were branded as witches and burnt at the stake!

But the real cause remained a mystery for many more centuries!

(To be continued...)
[/FONT]
 
[FONT=comic sans ms,sans-serif]Tin # 2.

The real cause of Tin Plague.

Only after the discovery of X rays, and the crystalline structures of the metals were studied with the X rays, the cause of the Tin Plague was discovered!

Tin and a few other metals, had different structures at different temperatures.At the room temperature and higher temperature, Tin was in its most stable form as White Tin. At temperatures below 13 degree Celsius, Tin's crystalline structure started changing, leaving more space between its atoms and Gray Tin was formed.

Gray Tin lost its metallic properties and became a semi conductor.The internal stress at the places of contact between the different crystalline lattices caused it to disintegrate and crumble into a gray power.

The lower the temperature, the faster the rate of disintegration.The disintegration is fastest at - 33 C.

The cause of the Tin Plague which baffled the scientists for centuries was at last discovered using the X rays. The sub zero temperatures prevailing in Russia was the real culprit and none of those young women mercilessly burnt at the stake as witches!

(To be continued...) [/FONT]
 
[FONT=comic sans ms,sans-serif]Tin # 3.

An injection for Tin Plague!

Just as we have appropriate 'shots' for flu and fever, scientists have discovered an injection to make Tin immune to the Tin Plague. An injection of Bismuth provides the Tin lattice with additional electrons. These electrons make the crystalline structure more stable -ruling out the possibility of the Tin Plague.

Tin has chemical resistance to Oxygen, water and organic acids. Salts of Tin are perfectly harmless to human beings. So Tin is best suited for canning.Tin has another name- The canning metal.Tons of fish, vegetable, fruits and meat are preserved using Tin.

In olden days the surface which had to be coated with Tin, would be cleaned and dipped in molten Tin. In modern times, electrolysis is used to deposit a layer of Tin of required thickness.

Pure Tin can talk! When the bars or plates of pure Tin are bent, they produce a crackling noise and talk to us.The friction between the different layers when Tin is deformed produces the sound. But when alloyed with the other metals, Tin becomes silent.

Tin has a very low melting point 232 degrees C. Alloys of Tin can have even lower melting points. These alloys are useful to make the electrical fuses-which melt and stop huge current flowing through them.

(To be continued...)[/FONT]
 
[FONT=comic sans ms,sans-serif]Tin # 4.

Uses of Tin.

Compounds of Tin are widely used in technology.Tin Chloride is essential in dying cotton and silk threads.Stannus Chloride is used to give a red tint to glass and porcelain.

Gold paint is nothing but Stannic Sulfide. Smoke screen created during a military operation is produced by the action of water on Stannic Chloride.

Bronze, an alloy of Tin and copper is much stronger than both Tin and Copper. Tin's Latin named "Stannum" is derived from the Sanskrit word "Stan" meaning hard. But pure Tin is soft and does not deserve the name Stannum!

A bath of molten Tin is useful in making smooth glass surfaces which need no polishing. The glass is called Float Glass. Molten glass is poured on a bath of molten Tin and allowed to cool. The resulting glass is of uniform thickness and is highly polished naturally.

Glass coated with a layer of Stannic oxide has an unique property. It is as clear as the plain glass, since the Tin oxide layer is invisible. It lets in the Sun's light and heat but does not allow them to go out.

So the green house made of this Tin Oxide glass remains warm long after the Sun has set-even when the exterior temperature may be zero C or even less than zero C!

Tin Stone-Cassiterite- has been the main source of Tin since time immemorial.The biggest Cassiterite deposits are found in Malayan Archipelago.

A block of Tin 30cm x 20cm x 8 cm may look like an ordinary brick but would weigh a massive 50 K.G. Tin is finding new uses and is always short in supply. Geologists are searching for Tin Stone under water and under ground.

(Story of Quicksilver follows! ) [/FONT]
 
[FONT=comic sans ms,sans-serif]Mercury # 1.

The Exception to the rule!

All metals are solids, malleable, ductile and have shining lustrous surfaces. Did I say "all?" Well, it should have been "almost all" since we have a grand exception to the above rule...the one and only liquid metal found in Nature, called Mercury!

Mercury can be frozen into a silvery blue metal resembling Lead at (-) 38.9 degree C. Frozen mercury resembles a regular metal.

Mercury is the heaviest known liquid. One c.c of Mercury weighs 13.6 grams. A One liter bottle filled with Mercury will be heavier than one bucket filled of water!
Hard to believe? But it is true!

Most of the metals including Iron will float in Mercury like a piece of cork or wood!

Mercury has been known since prehistoric times. Aristotle has referred to Mercury.Its Latin name is Hydrargium- meaning Silver Water or Quick Silver.

Mercury has been associated with several medical properties. Mercuric chloride disinfects. Calomel is a laxative. Mercusal is a diuretic. Mercury ointment cures skin diseases.

Mercury and its vapors are highly poisonous.Mercury occurs as tiny droplets in nature. Cinnabar-the beautiful blood-red-spotted stone is its main ore.Working with Mercury is not a pleasant prospect. Teeth would crumble first and death would follow.

So dogs are employed to find Cinnabar. Dogs don't complain or fight for compensation. Hence man has as usual ingeniously shifted the hazardous part of the job on to the poor unsuspecting dogs!

(To be continued...)[/FONT]
 
Mercury # 2.

 Amalgams of Mercury.

Copper rubbed with Mercury acquired a silvery tint. A man working in the court of King Henry VI passed on Mercury coated copper coins as silver coins-pocketing a huge profit!

Thieves had been there all along in human history-using science as a valuable tool!

Alchemist produced Gold from Mercury! While demonstrating to the gullible public, a few grains of gold would be placed in the crucible-unknown to the public.

Mercury would be poured and stirred with a wooden spoon. The grains of Gold would dissolve and show as traces of gold in the Mercury.

People would be surprised that transmutation had taken place right under their noses! But a scary death awaited such swindlers!

Sooner or later the word would spread. He would be summoned by the King to mass produce gold in the court .If too proud to confess of malpractices, the alchemist would be hanged in a gilded gallows wrapped in a metal spangled robe!

A colorful death for a colorful cheat? Apparently this did not deter many adventurists!

Mercury can combine with many metals forming their amalgams.This principle was utilized in depositing a very thin layer of gold on the copper church cupolas.

Gold would be dissolved in mercury. The workers would degrease, clean and polish the copper surfaces to be gilded with gold.

The amalgam would then be be applied.The cupolas would be heated in special braziers to make the mercury evaporate-leaving a thin gold film on the cupola.

The bluish green mercury vapor emerging from the braziers were highly poisonous to the workers. Many precious lives would be lost before a church could thus get gilded!

Today amalgams are used to make mirrors, in laboratories and in industries.

(To be continued... )
 
[FONT=comic sans ms,sans-serif]Mercury # 4.

Uses of Mercury.

Mercury is used in the production of Chlorine, Caustic Soda, synthetic acetic acid etc. Quartz Mercury lamps can produce powerful ultra violet radiations to purify the air in the operation theaters. It is also useful in Radiotherapy.

Mercury vapor lamps give out white light-closest to the day light. Mercury is best suited for use in thermometers. It is opaque. It shows well through glass. It expands uniformly over a large range of temperature.

Medical thermometers have a capillary measuring 0.04 m.m..The capillary is made in the shape of a prism which magnifies the mercury column for easy viewing. The white enamel coating forms a screen at the backside.

Glass is brittle and breakable. But it can't be replaced by the transparent plastic- which has many tiny pores-which would let air in and prove destructive to mercury in it.

Mercury ores are roasted in earthen pots. The vapor condenses to give mercury. Modern methods employ remote controls to avoid the highly dangerous mercury poisoning in the workers.

( The story of costliest metal known follows...)[/FONT]
 
[FONT=comic sans ms,sans-serif]Platinum # 1.

Platinum -The poor quality (?) Silver

Spaniards kept looting the Aztecs and Incas repeatedly of their gold, silver and emeralds. One detachment moving along the river Pinto in Colombia, discovered gold and an unfamiliar silvery metal.

It was heavy and a had a very high melting point-making it useless for all practical purposes! It was called Platina del Pinto-the poor quality silver.

Platinum was sold cheaper than silver. But soon Spaniard jewelers discovered that platinum can be malted easily along with gold. The started using Platinum with gold in making jewels which were thought to be substandard.

Their king got very annoyed and waned to get rid of the possibility of this kind of substandard jewelry. He got the brainwave of dumping all the platinum into the sea in the presence of witnesses.Another Mohamed Bin Thuglak with his very original solutions to grave problems! So all the precious metal was dumped deep into the sea.

Platinum is usually accompanied by several other metals. They are together called as the Platinum metals. A study of platinum resulted in the discovery of these other metals.

Palladium and Rhodium were discovered in 1803. Osmium and Iridium were discovered in 1804. Ruthenium was discovered in 1844
.
Soon platinum was put to practical uses. Platinum retorts can store concentrated sulfuric acid! Crucibles, pipes, bowls and sieves were made of platinum. It became a good catalyst in many reactions.

(To be continued...) [/FONT]
 
[FONT=comic sans ms,sans-serif]Platinum # 2.

Modern uses of Platinum.

A very thin layer of platinum deposited on a glass makes it a one way mirror. It is refracting one side and reflecting on the other. In other words it is a partial mirror.

It reflects objects on the side where the source of light is situated. The reverse side is transparent like glass. All the objects beyond it are clearly visible. Platinum mirrors are very useful in the lower stories buildings and in private apartments- making the use of curtains unnecessary.

Platinum is finding wider application in medicines. It is widely used in dentistry since it is non toxic. Jewelers show interest in platinum ever since it has become costlier than gold.

For those who want to keep abreast with the latest trend and style but do not have the necessary money power, platinum alloy jewels are available .. looking as good and making the wearer feel as great as the original platinum jewels do!
[/FONT]
 
[FONT=comic sans ms,sans-serif]Morals from the stories of metals.

It has become a compulsive habit for me to draw some useful conclusions/result/morals from what I read/write or even think about. So here are some morals drawn for the stories we have just read.

1. Lead:
It is freely found in nature and in large nuggets too. It is easy to melt it and shape it. So it was widely used regardless of the fact that it was highly poisonous!

"All that is easy to handle and freely available may NOT do you any good!"

2.Gold:
It is valued from its "cradle to coffin". It is the precious metal whose life is inseparably connected with murders, mistrusts and massacres. Poor Gold itself is a perpetual prisoner.

"We may envy some people for their beauty, riches and achievements. But surely they too have their own headaches and problems!"

3.Silver:
It has been more or less steadily valued and is the most useful metal by it purifying property and good looks!

"Some people are born great and remain great throughout their lives".

4.Copper:
The most versatile metal! The most useful component of many useful alloys. When it is a statue it is considered as the wonder of the world. Broken by an earthquake it is considered as a scrap metal.

"When the great people fall from their place of honor, they fall harder and harsher than the rest of the people"

(part 2 follows)
[/FONT]
 
[FONT=comic sans ms,sans-serif]Morals from the stories of metals.(Part 2)

[/FONT][FONT=comic sans ms,sans-serif]5. Iron:
The most useful metal of divine Origin. Hard to imagine how man lived without it more than 5000 years ago!

"Some people achieve greatness and remain great despite the young, active and new challengers"

6.Tin:
Is Very useful, harmless and always short in supply!

"The good people-sweet and harmless-are liked by everyone but seem to be always short in supply"

7.Mercury:
The most attractive metal. It may break up into 1000 small droplets- each one a perfect sphere! But they will combine again to form the big drop without any reservation or hesitation.

"Men should be able to unite as easily as the tiny droplets of Mercury and at the same time each of them must learn to retain his individuality"

8. Platinum:
The metal which was considered as useless and dumped into the deep sea! Now it is costlier than even gold!

"You are what you are-whatever the others may think about you or talk about you or nickname you. If your worth is not realized by them, it is their fault-not yours!

So just be yourself at all times and at all places"

Just BE ["asi"] and Do not BECOME ["bava"].
[/FONT]
 
[FONT=comic sans ms,sans-serif]Dear friends!

The unusual stories of the Magnificent Seven and the latest addition Platinum concludes with this post.

But the thread will not be closed!

Remember the heading is "Did you now that...?"

So I can bring in here anything interesting-as and when I find them.

Hope to find something soon enough!

A small request to all the readers.

Except Mr. C.Ravi who promptly gave his opinion as soon as the thread was started and Mr.Brahmanyan during the posts on copper, the rest of you very quiet!

It will be good to get some feedback-any feedback-to keep me going on!

How would you like it if you go on talking to someone and you never hear a word out of that person?!

My position isn't much different here!

Looking forward for more useful suggestions, tips and feedback from all of you,

yours sincerely,
Visalakshi Ramani. :pray2:
[/FONT]
 
Strange but true!

Light can't be seen by us! Hard to believe? Isn't it?

Light makes the other objects visible whereas light by itself is invisible.

Sun's rays entering a room through a small hole will not be visible to us.

But the presence of dust and / or smoke in the air, will make its path clearly

visible.

When it falls on the floor it lights up a small patch on it.

Sun, Moon the Stars and even the little firefly are luminous bodies giving out their

own light.

Non luminous objects become visible when they scatter or reflect the light rays

falling on them.
 
Strange but true!

Smooth surfaces reflect while the rough and irregular surface scatter the light

rays.Hence they appear equally bright seen from various angles and positions.

A transparent crystal when powdered becomes opaque - due to this kind of

scattering of light.

Rain clouds are in fact transparent since the water vapor and air in them are both

transparent. Yet the clouds appear black or dark colored. Why?

It is because they scatter the Sun's rays upwards and do not allow them to reach

our eyes. So the rains clouds appear black.
 
Strange but true!

Infinite Images.

If two highly polished mirrors are set parallel to each other and if you stand in

between the mirrors, you will find an army of people-all of them resembling you-

in both the mirrors!

If you smile they all smile back at you! If you frown they all do the same!

Must be an interesting experience!

Theoretically infinite images will be formed.

But in practice the images become duller and duller due to repeated reflections.
 
Strange but true!

Did you know that metals also evaporate?

Water evaporates giving rise to water vapor.

Can you believe that metals too evaporate?

When metals evaporate they release electrons into the air.

The surface barrier of the metals controls the free electrons

from escaping from the surface.

But just as an increase in the temperature makes water form more vapor rapidly,

an increase in the temperature releases more electrons from the surface of a

metal.

This is called Thermionic Emission and the electrons are called Thermions.

Volatile liquids evaporate very fast. Other do at slower rate.

In the same way different metals evaporate releasing Thermions at different

rates. Interesting ! Isn't it?
 

Why do our eyes get tired when we read/ write for a long time?

Human eyes are designed to see the far away objects rather than the nearby

ones. While looking at the far away objects, the ciliary muscle holding the lens are

at ease. There is absolutely no strain and we can watch things far way for a long

time.

But when we read/ write/ type/ watch T.V. etc the eye lens has to change its focal

length to be able to see the nearby objects clearly using the Power of

Accommodation of the eyes.

This is done by pulling down the ciliary muscles in order to make the lens thick.

So this continues for long periods the eyes tire very easily.

This can be reduced by taking short breaks and looking at a far away object.
 
Charged bodies!

When a glass rod is rubbed with silk, it loses a few electrons and acquires a positive charge.

If an ebonite rod is rubbed with wool, it picks up a few electrons and becomes negatively charged.

These two rods are now having a positive and a negative potential respectively.

They are having static electricity as charge.

At the first available opportunity the charge gets earthed and the rod becomes neutral.

The crackling sound we hear when a polyester sari is unfolded is due to static electricity. If we walk barefoot on a fluffy carpet we develop static electricity.

When we touch the metal knob on the door, we feel a mild shock since the charge passes through the door knob to the ground.
 
Higher to lower level.

When two different things are mixed together and if they differ in terms of their levels in any property, there will be a flow from the higher level to the lower level, until they both are equalized.

So when two water containers kept at different level are connected through a tube, the water from the higher level will flow to the lower level, till the two levels become equal.

When objects at two different temperatures are mixed the heat from the hotter object goes into the cooler one, till they reach the same temperature.

In the same way when two points at different potentials are connected, current will start flowing from the higher potential to the lower potential through the connected gadget or wire.

Obviously the Positive is the higher potential and the Negative the lower potential.
 
The inevitable zero.

For measuring the height of a mountain, the sea level is taken at the level of reference or level zero.

In the same way the potential of the earth is assumed to be always zero.

When a positively charged conductor is connected to the earth, current flows from the conductor to the earth until it becomes neutral.

If a negatively charged conductor is connected to the earth, current flows from the earth to the conductor until it becomes neutral.

So earth can accept the excess charge and give away deficit charge but is always at zero potential!

It is pretty much like the Poornam which does not get increased by any additions or get diminished by deletions!
 
[FONT=comic sans ms,sans-serif]Earth as a giant magnet.

Magnets have this strange property-like many human beings! Like poles repel and unlike poles attract. A magnet hung freely always points to the North-South direction.

The North pointing pole of the magnet is its North pole and the South pointing pole the south pole of the magnet.

So the magnetic south pole of the giant magnet called Earth lies very close to its geometric north pole. So also the magnetic north pole of the earth lies very close to its geometric south pole.

The lines of force of any magnetic field stars from its north pole and end in its south pole. In the case on the earth they start from the geometric south pole and culminate in the geometric north pole.

May that is the reason we are forbidden to sleep with our head placed towards north!

Is it because all the lines of force of earth's magnetic field culminating on our dense domes and disturb our sleep and equanimity of our mind?
[/FONT]
 
The lightning conductor.

Thunderstorm is the result of two oppositely charged clouds coming together. The current flows from the positively charged cloud to the
negatively charged cloud- breaking the air resistance.

No wonder the lightning is always accompanied by crashing sounds and blinding streaks of light.

Sharp points attract the charges in the clouds better than rounded objects.

Taller objects attract the lightning since the distance it has to travel to the earth is reduced.

Even Nature prefers shortcuts and easy paths.

The tall buildings have lightning conductors kept high above the buildings. They have spikes on the top of the rods . The rods are connected to earth offering very little resistance to the flow of current.

The spikes attract the charges in the clouds and let them get earthed without causing any damage to the buildings.

Earth is the huge reservoir of charges but is always at zero potential.
 
Temples and thunderstorms.

In olden days, no building would be taller than the local temple. The kalasam kept on the top of the temple acted as the lightning conductor.

Our ancients used the same word 'bijli' to denote current and lightning. So long before Benjamin Franklin proved-risking his life-that lightnings were electrical in nature, our ancestors knew that fact but made no great fuss about it.

There is an old adage which says
"Do not live in a place which has no temple".

With no temple kalasam to arrest the lightning, it can land anywhere on the village / town.

The palm leaves are spiked and face skywards. The trees are very tall.

Small wonder that lightnings more often than not lands on palm trees - leaving them partly or fully charred!
 
Status
Not open for further replies.

Share this page

Share this page

Latest posts

Latest ads

Follow us on Social Media

Back
Top