My Science School

          Kalidasa was a famous Indian poet and dramatist. He was a master of Sanskrit language and perhaps the greatest writer of any Indian epoch. He is usually compared with Shakespeare, the great English dramatist.

          Kalidasa was known to be a Brahmin who was orphaned in childhood and brought up by a cowherd. He did not receive any formal education for eighteen years. Then, as luck would have it, he came to marry a princess — the marriage being brought about by a minister of the princess’s father, with a view to teach her a lesson! The boy was introduced as a learned Pandit. When the princess came to know of the truth, she was highly distressed. She insisted on Kalidasa acquiring higher education by pleasing goddess Kali. The goddess took pity on him and blessed him. Soon Kalidasa became a very learned man and a great poet. He called his wife as his ‘guru’.

          As legend goes, Kalidasa was one of the nine distinguished courtiers of King Vikramaditya of Ujjain. He lived sometime between 170 B.C. when the Sunga King Agnimitra ruled and 634 A.D. to which Aihole inscription dates. Many scholars opine that Kalidasa was present during the reign of Chandragupta II (380 A.D. - 415 A.D.). According to a Sinhalese account, he died in Ceylon during the reign of Kumaradasa in the 6th century A.D.

          Kalidasa was probably a very cultured man, full of humour and buoyancy. He had high esteem for women.

          There are seven famous works of Kalidasa — three plays and four long poems. All of them are in Sanskrit. 

          Abhijnana Shakuntalam (“Shakuntala recognized”) is regarded as his greatest play, and usually judged as the best Indian literary effort of any period. Taken from an Indian legend, it tells of the love between the nymph Shakuntala and King Dushyanta, his rejection of the girl and his child and their subsequent reunion in heaven. The work is important because of the child, Bharata, after whom Bharatvarsha came to be named.

          The second play Vikramorvasi (‘Urvasi won by valour’) tells of a legend as old as the Vedas. Its theme is the love of mortal for a divine damsel.

          The third play is Malvikagnimitra. Three famous long poems of Kalidasa are Raghuvansa (Dynasty of Raghu), Kumar-Sambhava (Birth of the War God) and Meghaduta (Cloud Messenger). The first recounts the legends of Rama’s forebears and descendants. The second tells the story of Siva and Parvati. The third deals with the message of a lover for his absent beloved. The fourth one is the Ritusamhara (The Garland of the Seasons) — perhaps an early work.

          Kalidasa’s works reflect on the aristocratic society, sure of its dignity and power. To him goes the credit of exploiting Sanskrit to the full. Till today he is regarded as unrivalled by any other Indian writer. 

          Magnetism owes its name to the fact that the early Greeks found the natural magnetic material called Lodestone, in an area called Magnesia, a province of Asia Minor in 800 B.C. This stone was of black colour and an ore of iron called magnetite. This stone has several interesting properties.

          Firstly, it has a strong attraction for iron. On experimenting, it was found that if a piece of lodestone was dipped in iron fillings and then lifted out, the fillings mainly get attached to certain parts, the other parts remaining bare. These regions of greatest attraction were called the poles and the place where there was little attraction was called a neutral region.

          It was also discovered that if a piece of lodestone was suspended by a thread or floated on a piece of wood, it came to rest in a definite direction — pointing towards north and south. The part pointing towards the north was called the North Pole, and the one pointing towards the south was called the South Pole. This property was used by the Chinese in the 13th century to make use of magnets as compasses for finding the direction in sea voyages.

          Experiments in this field further revealed that if two lodestones were brought together, the north and south poles attracted each other while the north-north and south-south poles repelled each other. This established the fact that dissimilar poles attract each other and similar poles repelled each other.

          If a bar of iron or steel is rubbed from one end to the other end with a piece of lodestone, it also acquires magnetic properties and becomes a magnet. Such a magnet is known as an artificial magnet.

          Gradually scientists working in this field also discovered that a magnet could be made by winding an insulated wire around a piece of iron and passing an electric current through it. This is called an electromagnet. Such magnets are used in electric motors.

          The next important discovery in the field of magnetism came in 1600. The English scientist, Sir William Gilbert, suggested that the earth was a giant magnet. Thus he explained why a freely suspended magnet points to the north and south of the Earth. 

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A kaleidoscope is an optical instrument used to produce symmetrical geometric patterns on carpets, sarees, wallpapers etc. It is also an entertaining toy for the children.

Kaleidoscope was invented by a Scottish physicist, Sir David Brewster in 1816. It illustrates the image forming properties of combined inclined mirrors by successive reflections. If one object is placed between two plane mirrors, at right angles to each other, three images are produced by successive reflections. Similarly, if the mirrors are inclined at 60°, five symmetrical images are formed.

A kaleidoscope consists of three strips of mirrors inclined at an angle of 60° to one another. They are enclosed in a cylindrical tube. One end of this tube is closed by means of a piece of ground glass, while the other is closed by a piece of cardboard with a hole at its centre. Several multi-coloured glass pieces and beads are loosely enclosed between the three inclined mirrors with the help of a disc made of plane glass. Now when viewed through the hole of the cardboard, along the axis of the tube, a symmetrical pattern of images of the coloured glass pieces are seen.

When a person turns the kaleidoscope, the coloured glass pieces and beads change positions, thereby new patterns are produced. And so in this manner, an infinite number of combinations and patterns can be formed. The tubes used in most of the kaleidoscope are usually 25cm in length and 5 - 8cm in diameter. It is a very useful instrument for the designers. 

          Litmus is used in chemistry to detect the presence of alkalis and acids. Litmus is a dye made from small plants called lichens. It is either red or blue in colour and is used in the form of a solution which is sometimes on a test paper.

          When lichen called Rocella Tincotoria is allowed to react with ammonia, potassium carbonate or lime, it gives a blue colour material. The paper is dipped into it and dried. This is known as a blue litmus paper, and is used to test acids. Acids turn blue litmus red.

          Orchil or cudbear is a red dye obtained from another species of lichens. This is used to make red litmus paper. Alkannet or alkanna is another dye obtained from the root of the plant Alkanna Tinotoria. The colouring ingredient, alkannin, is soluble in alcohol, benzene and others. When white paper is impregnated with an alcoholic solution of alkannet, it becomes red. This red paper is turned blue or deep violet by alkalis. 

          Neutral solutions (neither acid nor base) do not change the colour of litmus.

          When a chemist wishes to neutralize an acid solution, he first adds litmus solution. This changes its colour to red. The base is then added, until its colour changes to violet. The solution then becomes neutral, i.e. neither base nor acid and one more drop of base turns the solution blue.

          When acids and bases react, they produce salts by neutralization. For instance, the common salt that we use in our food is produced by the reaction of caustic soda and hydrochloric acid.

          Nowadays, litmus paper is made from several substances such as azolitmin, crysthrolitmin, spaniolitmin etc. These are apparently mixtures of closely-related compounds that were identified in 1961 as derivatives of the heterocyclic compound phenoxazine.

 

          The Panama Canal and the Suez Canal are the two most important man-made waterways of the world. The Panama Canal is an inter-oceanic waterway connecting the Atlantic and Pacific Oceans through the Isthmus of Panama. Ships sailing between the east and west coasts of the United States shorten their journey by about 8000 nautical miles by using this canal!

          The history of the Panama Canal construction is very interesting. In the 16th century, the Spanish conceived the idea of constructing a canal across the Isthmus. In 1846 the United States concluded a treaty with Columbia. In 1855, the United States extended financial help for the project. The Panama Canal company was formed which was headed by Ferdinande Lesseps — the builder of the Suez Canal. However, within ten years due to faulty planning, graft and the ravages of yellow fever, malaria and cholera, the company became bankrupt. In 1894, the new Panama Canal Company reorganized the work, but made little progress due to lack of money: Following Panama’s declaration of Independence from Columbia in 1903, and the conclusion of the Hay-Bunau-Varilla Treaty between USA and Panama the canal building rights passed into U.S. hands. Work began in 1904 and finally the Canal was completed and first opened to traffic in August 1914. Since then many additions have been made. Its length is about 82 km. On 31st December 1999, Panama will take over full control of the canal from US. 

          The Canal consists of short sea-level sections at each end, three pairs of locks that lift ships to 26m above sea level, a 32 mile elevated section that includes Gatun Lake and a narrow eight-mile long excavated Channel, known as Gaillard Cut, running through the continental divide. The dimensions of its lock chambers (1000 ft in length, 110 ft in width and 41 ft in depth) permit most commercial ships as well as main navy ships to pass through the canal. Only very big ships cannot pass.

          The canal locks operate by gravity flow of water from Gatun and Madden lakes. The locks are of uniform length, width and depth and permit simultaneous transit of ships in either direction. Each lock gate has two leaves 65 ft wide and 7 ft thick, set on hinges. The gates range in height from 47 to 82 ft. Their movements are controlled by motors. They are operated by a control tower.

          The ships, including the waiting time, require 15 hours to negotiate the canal. Once a ship has been authorized to proceed, the average transit time through the canal, however, is seven to eight hours in deep water. The traffic through the Panama Canal has raised from 807 transits in 1916 to 15,523 transits in 1970. The cargo carried in 1970 amounted to 132,500,000 tons. Presently, average transits of ships carrying goods have been increased manifoldly.

          The Canal has helped to reduce greatly the travelling distance for ships. Ships no longer need to go around Cape Horn to go from the east to the west coast of America. From one coast of North America to ports on the other side of South America, the distance has been shortened by 3500 miles. Ships sailing between Europe and East Asia or Australia save about 2000 miles by using the canal.

          In view of the increasing size of bulk carriers and container ships and the inability of the present canal to accommodate the large aircraft carriers of the U.S., there have been proposals to expand the present waterway. 

 

          Confucius was one of the greatest moral teachers and philosophers of China. He studied ancient Chinese writings with great devotion. These works taught him many new ideas about character development. In Chinese his name was ‘Kung Fu-tzu’. This name was distorted by the catholic missionaries and became Confucius.

          Confucius was born in the state of Lu, now part of Shantung in China. His family belonged to the lowest level of the aristocracy. His parents died when he was still young, and he grew up in poverty. Later, he became an official in the government of Lu, and was much respected.

          China, during those days, was ruled by an Emperor who was a mere figurehead with very little powers. The provinces were controlled by corrupt and greedy feudal lords. The people were poor and neglected. Confucius felt disgusted at this state of affairs and left Lu in 484 B.C. He started preaching whatever he had learnt from the ancient Chinese writings. Human behaviour, morality and politics were the main elements of his teaching. At the age of 22, three years after his marriage, Confucius had started teaching how to lead a happy life. He said, ‘Don’t do to others, what you would not wish them to do to you’. He taught ‘Thou shalt love thy neighbour as thyself’. He was a modest man who always said ‘I teach nothing new. I only pass on the ancient wisdom’.

          When he returned to Lu, he also held some important positions in the local government of his province. When he was made the governor of a city, he cleared the state of robbers, reduced taxes, improved people’s living conditions and persuaded the ruling classes to lead charitable lives. According to one account, he was also made a minister. He tried his best to remove the evils ingrained in all branches of social life. But soon he realized that they were deep-rooted. So he resigned in disgust at the age of 54.

          Confucius’ own sayings were collected by his disciples and written down much later, in the book ‘Lun Yu’. Confucius died in 479 B.C.

          The religion founded by him is known as Confucianism. It includes ancestor worship, belief in the Supreme God and belief in nature spirits. Even today it influences millions of lives.

 

          Ultraviolet rays are electromagnetic waves that cannot be seen by the human eye. When sunlight is allowed to pass through a prism, it splits into seven colours. These colours are violet, indigo, blue, green, yellow, orange and red. Wavelength-wise distribution of the seven colours is known as spectrum. The ultra-violet rays form an invisible band, just outside the violet end of the visible spectrum. The band just beyond the red end is called infrared.

          Light travels in the form of waves. These waves are produced by electrical oscillations. The frequency or wavelength of each colour in the spectrum is different. Frequency is measured by the unit ‘hertz’. If a body vibrates once in a second, its frequency is said to be one hertz.

          In the seven colours of the sun’s spectrum, violet has the maximum frequency and red has the minimum frequency. In other words, wavelength of the violet colour is minimum, while that of red is maximum.

          The observed wavelengths in the visible spectrum range from about 7.5 x cm to 4 x  cm. Waves having wavelengths more than that of red light is called infrared waves. Infrared radiations comprise wavelengths ranging from 1 mm to about 7.5 x  cm. Waves having wavelengths more than infrared radiations are called microwaves. The range of microwaves lies between 1 mm to 30 cm. Waves with wavelengths more than those of microwaves are called radio waves. On the other hand, radiations having wavelengths less than that of violet colour are called ultraviolet rays. Ultraviolet rays lie in the wavelength range of 4 x  to   cm. Beyond ultraviolet rays come X-Rays which roughly lie in the wavelength range of   to   cm. Beyond X-Rays come gamma rays. As we go from ultraviolet rays to gamma rays the wavelength decreases or the frequency increases. As the frequency increases, the amount of energy associated with the waves also increases. Thus X-Rays and gamma rays are very high energy radiations.

          Energy associated with ultraviolet rays is also quite high. Overexposure to ultraviolet rays can cause skin burns, and may even lead to skin cancer. The sun produces a large amount of ultraviolet light most of which are absorbed by a gas called Ozone, in the upper atmosphere of the earth and as a result very small amount reaches the earth. If the entire amount of ultraviolet light were to reach us, life wouldn’t have been possible on earth.

         Ultraviolet rays are useful also but only in small amounts. They kill certain bacteria and help to change certain chemicals in the skin into Vitamin D. These rays are very harmful for the eyes as they cause eye-cataract. While working with ultraviolet light, one must wear coloured glasses. When these rays fall on certain substances, they produce fluorescence. 

          An Aurora is a beautiful pattern of light that can sometimes be seen in the sky at night. The sky gets a glow with brilliant green, red, blue and yellow colours. An aurora near the North Pole is called Aurora Borealis, or the Northern lights. An aurora near the South Pole is called as Aurora Australis or the Southern lights. Sometimes both the phenomena are called “Aurora Polaris”.  But what exactly are auroras?

          Systematic scientific studies in this field began in 1716, when a spectacular aurora appeared in Europe and was visible in the entire continent. The English astronomer Edmund Halley proved a relation between auroras and the earth’s magnetic field. The most widely accepted theory about their origin is as follows.

          We know that our sun is a hot ball of fire. It produces heat due to fusion reactions. As a result, charged particles like protons, electrons, etc. constantly flow out of the sun. The flow of these charged particles is called solar wind. These particles travel through space in all directions at a speed of 480 km per second. As they enter the Earth’s atmosphere, they are attracted by the Earth’s magnetic field. The magnetic north and south poles change the direction and speed of these particles. These particles then collide with air molecules in the cold, thin upper atmosphere. This causes ionization, resulting in the production of coloured lights. These coloured lights are called Auroras. 

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          Before the discovery of anaesthetics, an operation used to be an agonizing experience for the patient. Even though different agents like herbs, gases, oils and drugs were used for relieving pain, the patient sometimes died from pain and shock. It was only with the discovery of modern anaesthetics that a major break-through was achieved in the field of surgery.

          An anaesthetic is a substance that causes a loss of sensation or feeling in the body. The history of its discovery is very interesting. In 1799, the British chemist, Sir Humphry Davy inhaled some ‘laughing gas’ (nitrous oxide) and found that it produced unconsciousness. Davy published this experience and in 1844 in the United States Horace Wells performed the first dental operation using nitrous oxide as an anaesthetic. Two years earlier, i.e. in 1842, the first painless operation had been carried out by Craw Ford W. Long, using ether as an anaesthetic. In 1847, chloroform was reported to have similar anaesthetic effect. At last surgeons had found a method of overcoming pain to carry out lengthy operations without undue haste. 

          Today, many new types of anaesthetics have been developed. Their application is of two types: local and general. Local anaesthetics are used to numb a particular part of the body. They act by blocking the transmission of electrical impulses along nerve cells, and are usually injected around the nerves that normally carry impulses from the area to be operated upon. The first of these anaesthetics was cocaine. This was superseded by another drug called procaine in 1905. Numerous drugs related to procaine such as lignocaine are nowadays used.

            General anaesthetics render the entire body unconscious. Nitrous oxide, ether and chloroform are included in this category, together with a more recently developed drug, halothane. Once inhaled, they act within seconds but recovery starts immediately after the drug is withdrawn. Halothane has been found to have side effects on liver. Now it has been replaced by ethrane.

          Under general anaesthesia, the patient’s respiration may be controlled externally. There are two reasons for this. First, general anaesthesia depresses the area of the brain that controls respiration. Second, for many operations the patient’s muscles need to be released which is achieved by giving a drug called curare.

          A person called an anaesthetist is trained to give proper amounts of anaesthetic to patients being operated for different ailments. At least one anaesthetist is always present in the operation room during the surgery.

 

In times of war, soldiers use special helmets to protect their heads. While driving a scooter, the riders often wear helmets to protect their heads against any injury. In many cities the governments have even made the helmets compulsory for riders. Do you know why the protection of head is necessary?

The most important part of our body, the brain, is located in the cranium under the protection of bones. The human brain is divided into three main parts: the cerebrum, the cerebellum and medulla oblongata. It controls all the important functions of the body – sight, taste, smell, hearing, touch, movements, memory, speech etc. Any damage to brain can disturb the proper body functioning.

Our brain is protected by the thick bone of the skull. Further a shock absorbing fluid cushions it against the blows of bumps. But if the blow is sharp or hard enough it can injure the skull. Thus to protect the brain from injuries it is essential to first protect the head.

Now the question arises what may be the consequences of head injuries?

A severe head injury due to an accident may cause brain hemorrhage which eventually may lead to death. The injury may damage the memory unit of brain by which a man can loose memory temporarily or permanently. It has been often seen that after having a severe injury of head people remain in coma for long periods.

If the brain tissues are damaged it may give rise to multiple sclerosis. Parkinson’s disease is caused by a disorder of brain chemistry which may result due to head injury. Brain injury may cause aphasia, a serious disorder of thought and communication. Apart from these effects many other disabling conditions can be generated by head injuries.

It is therefore essential to protect the head against injuries.

          More than 60 years back typhoid epidemics used to claim thousands of lives every year. But now, on account of research and advancement in medical science it has been largely controlled.

          Typhoid fever is an acute infectious disease caused by the typhoid bacillus. In medical terminology it is called bacillus salmonella typhosa. It enters the body via contaminated food, water, or milk and finally reaches the blood stream. It infects the blood and poisons the system. Among its main symptoms are fever, cough, headache, skin eruption, enlargement of the spleen, and a fall in the number of white cells. There may also be a loss of appetite. Persistent fever develops which gradually rises, reaching up to 39.4°C or 40°C. After a spell of one or two weeks it starts falling. In about 30 days, the temperature becomes normal.

          Formerly, the treatment was entirely symptomatic and supportive. After 1948 specific treatment with antibiotics was developed which proved to be very effective. Medicines like Chloramphenicol or Tetracyclines provide suitable antibiotic therapy. Cold sponge baths help to control the high fever. In some severe cases, the doctor may even go in for blood transfusion or infuse blood plasma. 

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          In fact, crying is the baby’s first sound message. It is the first attempt of the baby to communicate with the world around him. As the baby is unable to put its feelings and desires in words, it communicates by crying!

          It is a matter of common experience that newborn babies cry a lot during the first few months. As the baby starts growing up, there is a marked decline in this practice. By the time the baby is two years old, this habit is almost gone.

          It is interesting to note that this practice doesn’t just express wants and discomforts like hunger or illness. Normally the tears do not appear unless the baby is really distressed. 

          Most mothers are able to distinguish between cries indicating hunger, anger or pain. They are able to tell, with some degree of accuracy what the baby wants. For example, if a baby is hungry, it will continue to cry even when fondled. But if it is crying from boredom, it will stop crying when picked up or when moved to other interesting surroundings.

          Recent studies have shown that if a mother is sensitive in this regard, and responds accordingly, the baby will cry much less by the end of the first year as compared to one who is not. Knowledge of the basic food-stuffs essential to a growing child is necessary to become an ideal mother.

          By the age of four or five months most babies start making certain special sounds. These sounds are called  babblings. It has been observed that babies enjoy these sounds.

          It is not always possible to know why a baby cries. There are occasions when the baby is neither hungry, tired, uncomfortable, bored nor frightened but still keeps on crying. However, usually the baby’s cries are meant to communicate some message.

          When a person falls sick, the doctor often examines his pulse by placing his fingers on the wrist of the patient. What does this pulse indicate?

          By pulse we mean the regular throbbing of arteries caused by the successive contractions of the heart. During the action of the heart there is a pause. During this pause the wall of the aorta contracts. This contraction forces the excess blood to proceed along the arteries. This alternate expansion and contraction of the aorta produces a throbbing in the arteries. This throbbing which can be felt at many points in the body, through the skin, is called pulse.

          The pulse can be felt by placing fingers on the wrist over the radical artery. It can also be felt at the temples where we have temporal artery or at other places where an artery is near the surface. This sensation cannot be felt in the veins because the blood reaches them from the arteries by passing through the narrow capillaries.

          The nurse or a doctor asks the patient to put the arm in a relaxed position with the thumb turned upwards. Then the doctor feels the pulse. The beats are counted for one minute. Since the pulsations mean the heart contraction, the pulse tells us about the heart rate. The pulse rate depends on the blood requirement of the body. This rate indicates how fast the heart is beating and the state of pressure in the circulatory system. An irregular pulse may indicate some abnormality in the functioning of the heart.

          The number of pulsations per minute normally varies from 78 to 82 among women and from 70 to 72 among men. The pulse rate in children is much higher than the healthy adults. The normal rate for a seven-year old child is 90 beats per minute. A new born baby can have a pulse rate of 140. The old people can be in the 50-65 range of pulse rate. 

            The human body is a machine that needs energy to work. This energy is obtained from food materials through metabolism. These metabolic processes are carried on by activating agents or catalysts called enzymes. Let us see what enzymes are and what they do in our body.

             An enzyme is an organic catalyst produced by a living cell. All enzymes are proteins made up of long chains of amino acids. They combine with the substrate to form an intermediate compound. This intermediate compound is an unstable complex, and breaks down to yield the reaction product, plus the original enzyme.

             Enzymes are themselves synthesized by other enzymes derived from nucleic acids. An average cell contains about 3000 different enzymes. In order to function correctly, many enzymes require the assistance of related substances known as co-enzymes which are produced from vitamins in the diet.

             The human body literally contains hundreds of different enzymes. Many are contained within the cells, but some others, such as those used for digestive purposes, act outside cells in the gut itself. Enzymes are involved in almost every chemical reaction taking place in our body.

             Many physiological activities such as digestion, building up and breaking down of tissues, cellular respiration and muscle contraction depend on their action. The activity of an enzyme depends on the temperature, the degree of acidity or alkalinity (pH) and the substance upon which the enzyme acts. A single enzyme molecule is capable of bringing about the required changes on hundreds of molecules of the substrate in a few seconds.

             Enzyme action can be blocked by some poisonous substances such as mercury, lead or arsenic. The presence of such substances hinders the enzymes from forming intermediate complex with the substrate. Normal metabolism is thus prevented.

            Enzymes are classified into six major groups: Oxidases which bring about oxidation, transferases which bring about group transfer; hydrolases which speed up the process of hydrolysis; lyases that bring about group removal. Isomerases enzymes are responsible for isomerization and ligases for joining of molecules.

           Enzymes are not only important for our body, but are also very useful in industry, medicine and analytical chemistry. Although enzymes normally work inside living cells still they are capable of working outside the cell. They are used to convert starch into glucose and glucose into fructose. They are also used in cheese-making industry and for the production of semi-synthetic penicillin. Artificial sweeteners are also produced with their help. 

          The biological process of speech requires the amazing co-ordination of larynx, cheeks, tongues and lips to produce sound. A person, who stammers, lacks of such coordination.

          Technically stuttering or stammering is known as dysphemia. In one form, the speaker cannot utter a word clearly – spasms occur in the speech muscles and he gets stuck with the first sound. So instead of saying mother, he would say ‘m - m –mother’. 

          The speech development of children starts with associating sounds with persons and objects. It is closely related to the association of auditory and visual symbols. Speech involves coordination of many aspects of brain functions. These areas in the brain, particularly those concerned with aspects of speech, are located in the dominant hemisphere of right-handed persons and in either hemisphere of left-handed people. Disease of these parts of the brain leads to characteristic forms of stammering.

          In another form, the muscles in the tongue, throat and face get spasms, and despite the fact that facial muscles work to make sound, no words come out. The face gets twisted.

          Stammering rarely shows up before the age of four or five. It mostly occurs after puberty. It is more common in males than in females. According to studies, the ratio between males and females is 4:1.

          Doctors and researchers are yet in dark about the definite cause of this disorder. However it is often connected with a physical disorder or some emotional disturbance. In either case it can be corrected to some extent by special training in reading and speaking. The person is taught to read and speak slowly and carefully, and breathe regularly while speaking. Hereditary predispositions of stammering have been noted in many studies. In one study about 40% stutterers were found to inherit this disorder.

          The treatment is difficult and it demands much skill and sense of responsibility on the part of the therapist. No medicines have so far been discovered for its treatment. However psychotherapy and speechotherapy have been found quite effective. In this, attempts are made to overcome speech difficulties, this is particularly important in children.

          Prevention of stuttering may even be aided through parent counseling. Parents can take care of their children in such a way that they do not develop the habits of hesitation, or syllable repetition etc. Parental guidance has also been found quite effective in reducing the number of stutterers. A very controlled, guided and conscious approach on the part of the stutterer often helps to redress the problem.