Transparent soaps are made of glycerin, and are partly soap and partly solvent. Sodium hydroxide causes crystals to form in soap, which is why the soap becomes opaque. In order to make it transparent, the soap has to be dissolved in enough solvent to make the crystals so small that light passes freely through, making the soap look transparent. There …

Some people become very frightened during a thunder storm, but there’s really nothing to worry about. Lightning is the result of a collision between two electrical charges one positive, and the other negative either in two clouds or in a cloud and the earth. When the difference between the two charges becomes great enough, a great spark the lightning jumps …

Most of us find telephones extremely useful for talking to others, but the telephone has several other uses. The telephone network sends voices around the world in the form of electric signals. It can also send other kinds of electric signals that are not voice signals for example, computer signals. Computer networks are groups of computers connected together by telephone …

Japanese legend says that the Sun-goddess Amaterasu ruled over the Plain of High Heaven, and her Storm brother’s empire was the sea Plain. But Susanowo, her brother, was so violent that Amaterasu hid in a cave and plunged the world into darkness. She peeped out when the gods hung a necklace and mirror in a tree, and light returned. Susanowo …

Diesel locomotive engines are classified as diesel-mechanical (DM), diesel-electric (DE) and diesel-hydraulic (DH) engines. DM engines run at an average speed of 60 kmph, while DE engines travel at an average speed of 80 kmph, also the average speed of an electric engine. The DH engines are heavy duty ones and maintain an average speed of 120 kmph.

They are air filled pockets within the skull and face bones and they are lined with mucous membrane. They open into the nose or mouth, chiefly, and they can quite easily get irritated or infected, which can be painful.

The vast coniferous forests in the northern hemisphere contain evergreen trees, including cedars, firs, larches, pines and spruces. They are all called softwoods, though some are quite hard. But most are easy to work and have many uses, including the making of paper. Deciduous, or broadleaved, trees grow in temperate lands. They include ash, beech, birch, chestnut, oak, sycamore and …

Around the continents are shallow seas covering the continental shelves. These seas contain most of the world’s chief fishing grounds, some of which are called banks. The Grand Banks, off the south-east coast of Newfoundland, Canada, extend across about 360,000 square km (139,000 square miles). With an average depth of 110 m (361 ft), they yield more than 800,000 tonnes …

They are a set of glands that manufacture hormones and introduce them into the body system. They differ from other glands in that they have no pipes for carrying away their productions, and are sometimes also known as ductless glands. They include the thyroid, the adrenal, the parathyroid, the pituitary, the pancreas, and the sex glands in both men and …

They refer to the new language developed by cellphone-addicted teenagers, based on predictive text on their handsets. They are also known as adaptonyms or cellodromes. Using predictive text, the first alternative to certain keywords are used in textonyms.