Why does Venice have canals? Venice is situated on a group of mud banks. These mud banks fonned more than 100 small islands at the head of the Adriatic Sea. The buildings in Venice are erected on pilings driven into the mud. In between the...
Who discovered atoms? John Dalton, an English chemist of the early 19th century, was the first man to come out with a scientific atomic theory. He found that elements are made of small particles called atoms. Later, Ernest Rutherford developed the idea of a solar-system...
What in the soil makes plants grow? The organic matter in soil comprises living things and their remains. The inorganic matter comprises minerals and rock particles. Humus, or decaying organic matter, allows more air and water to enter the soil. Dead organic matter also provides...
What is chicken pox? Chicken pox usually affects children but adults too can get it. It is caused by a virus and is very contagious. A patient is infectious for 14 days. The illness causes symptoms like fever, headache and a rash on the skin....
What is a weed? We know weeds as plants that grow where they are not wanted. Though dandelions are cultivated for fresh greens, they are out of place in a neatly manicured lawn and hence they are weeds. People living in the cities love wildflowers...
Who built the Tower of London? It was William the Conqueror who built the Tower of London. He did it to inspire fear in the people towards him. It was more of a prison than a fortress. The tower is still maintained as an arsenal....
What is Braille? Braille is a system that enables blind people to read. It was developed in 1829 by Louis Braille, a blind teacher. It consists of an oblong block on which raised dots are arranged from one to six. The Braille alphabet comprises different...
What is reincarnation? A Reincarnation is the transmigration of souls. Some people believe that after a person dies his soul leaves the body and enters the body of another living thing. Thus it is born again or reincarnated. The Egyptians and ancient Greek philosophers believed...
Who invented the paper clip? The paper clip is actually a recent invention. It was invented by Johan Vaalar in 1900. Vaalar worked for an invention office in Norway. Before it was invented people used to fasten papers by using pins or ribbons tied through...
When was plastic made first? Even as early as the mid-1800’s, chemists were aware of plastics. In 1909, Leo Baekland, a Belgian-American chemist discovered phenol-formaldehyde. It was a kind of plastic called thermosetting plastic. It was not easily soluble, could be moulded into any shape...
