108 items in this section. Displaying page 5 of 11
How do Flush Toilets Work?
Toilets are an amazing invention. Nearly every home has at least one. It is a very necessary utility needed in all homes to maintain hygiene. It is really amazing how this system works – you press a lever or pull a chain and whoosh! About two gallons of water rushes down into the porcelain bowl in three and four seconds. Gurgle-gurgle-urp it is clean and ready for use again! Toilets were known in India as early as three thousand years ago!...
Who Invented Traffic Lights?
Long before roads needed traffic lights, railways were using a system of signals to control train traffic. In the early railways, a single track was used for both up-going and down-going trains, and safety depended on spacing the arrival and departure of trains according to time intervals. These signals consisted of a ball and something that looked like a kite. When the kite was raised on top it indicated danger while if the ball was raised, it indicated the all clear....
What is Mad Cow Disease?
In 1996, doctors detected 10 cases of a rare and fatal human brain disease in Britain and they diagnosed that it was probably due to eating beef from animals with “mad cow disease”. Scientifically, this cow disease was termed bovine spongiform encephalopathy or BSE while the disease affecting humans was termed Creutzfeldt-Jakob disease (CJD). The disease caused panic in Europe both among people eating beef and the farmers who were selling it. The European Union, which is the administrative body and includes all countries in Europe, responded immediately by banning imports of British beef....
Why are Some Reptiles Brightly Coloured?
Most animals have skin colour that makes them merge into their surroundings. They become near invisible unless you look very closely. But some reptiles such as the sea-snakes, coral snakes and frogs of Central and South America are brilliantly coloured or have bright bands like deep yellow, orange, pink on their bodies. They are easily visible among the green leaves or brown earth. This is because these animals are poisonous. The colouring is a warning to other animals, especially their natural enemies, to avoid eating them....
How Did Santa Claus Originate?
Its nearly midnight and with a jingle of bells a sled comes streaking from the north, pulled of course by Rudolph, the red-nosed reindeer. Sitting in the sled is a jolly round red robed figure with flowing white beard and a bag slung over his shoulder that lands on the rooftop with a merry ho-ho-ho. Hey! Its Christmas and its Santa Claus. If you’ve been nice, he slides down the chimney and loads up little stockings hung there with lots of toys and goodies....
What is Blood Pressure?
The heart is a live pump that delivers blood to different parts of the body. Blood flows in or flows out when the heart contracts and expands. The blood is forced into the arteries, which expand to receive the oncoming blood. The force with which the blood moves through the arteries is knows as blood pressure. The arteries have a muscular lining which resists this pressure. The blood is thus squeezed out into smaller blood vessels....
How do Human Cannonballs Fly?
Even been to a circus where they featured a human cannonball? A person enters a huge cannon and when the fuse is lit, he comes shooting out with a bang, flying in the air before landing on a net! My god! I thought that was the most horrifying thing I had ever seen. What a crazy thing to do. How does he do it without being blown to pieces, I would wonder. How do Human Cannonballs Fly?...
What are the Various Jazz Styles?
Jazz originated from the American South in the 18th century as a form of music sung by African slaves employed in the many plantations. Jazz music was influenced by different cultures from a combination of African folk music and rhythms to Caribbean and black American music. Various styles of playing evolved in the 19th and 20th centuries as musicians started to improvise. This was because early musicians did not have formal training in Western classical music and those that did began to introduce European harmonies and forms into Jazz and made the pattern of music uneven....
Why are Eggs Oval?
Have you ever climbed a tree and peeked into the nest of a crow or a sparrow? Or looked into that flowerpot where the noisy pigeon decided to lay its eggs? The sight of a mother hen sitting on a bunch of fresh white eggs is great, though most of us see them only when they land on the breakfast table every now and then. Eggs come in different colours. They may be blue, blue-green, yellow, spotted, blotched or white....
Where are the Shaking Minarets?
Among the many architectural marvels of the world, like the leaning tower of Pisa, the whispering gallery at St Paul’s Cathedral at London or the musical pillars of South India, are the astonishing and historical shaking minarets of Ahmedabad, in Gujarat state, India. The minarets are so unique that if one minaret in shaken, the other sympathetically shakes too! Barely a kilometre away from the Ahmedabad city railway station is the Sidi Bashir mosque (Muslim equivalent of a temple) famed for its jhulta minars or shaking minarets (tall tower-like structures, either at the entrance gate or on the four corners)....