How did the grapefruit get its name? The grapefruit is twice the size of an orange but it is named after the grape. The reason is that the fruit hangs down in clusters like grapes. The clusters may include 3 to 18 fruits. The grapefruit...
Who were the Mayans? The Mayans were native Indians who built a huge empire that included parts of Mexico, Guatemala, and Honduras in the jungles of North America. The Mayan civilization reached its peak from 300-800 AD. But over the following two centuries it collapsed.
How did the Romans protect their cities from enemies? During the later phase of the empire, the Romans often faced attacks from the barbarian hordes that invaded Europe. So, to protect their cities, they built thick walls around the towns as well as forts so...
When did fish develop? The first fish were living in the seas about 500 million years ago. They did not have jaws or fins. Fish which evolved later like dunkleosteus were large predators. It was an armoured giant about 10 m long and its jaws...
What did Roman soldiers wear? The Roman soldiers wore armour consisting of metal strips which were joined together with straps over a woollen tunic. To protect the lower part of the body they carried a shield. When they were travelling they carried their weapons and...
Were dinosaurs cannibals? Some dinosaurs may have been cannibals. In New Mexico, fossil remains of the dinosaur, Coelophysis were found. Inside them were skeletons of young ones. They did not seem to be those of unborn babies. So it is believed that the adults ate...
What is taxidermy? When we visit a natural history museum we can see exhibits of animals, birds and reptiles which are ‘stuffed’ and placed there. The art of mounting birds, animals, fish and reptiles is called taxidermy. It has been prevalent for roughly three centuries....
What is a cyclone? A cyclone is a kind of storm which can wreak havoc on land sometimes. Storms are caused when warm, moist air from the equator moves into the northern hemisphere and encounters a mass of cold, dry air moving south from the...
What is incense made of? Incense is a compound of gums and spices. When it is burnt it produces fragrance. Frankincense, a gum resin from a tree, is the base of most kinds of incense. Other materials are also used to make it. Bark, wood,...
What makes silver tarnish? Silver is a precious metal like gold and is the whitest of all the metals. It also reflects light better than other metals and hence is used as the backing material for mirrors. It reacts very strongly to sulphur and many...
