In this video, you can listen to the interesting real life story of how foreknowledge of lunar eclipse on 29th Feb 1504 helped Columbus exploit the innocence of natives of Americas (Jamaica) to get access rights to their territory and also to get them feed all the Spaniard sailors accompanying him.
Bordeaux mixture (also called Bordo Mix) is a mixture of copper(II) sulphate (CuSO4) and slaked lime (Ca(OH)2) used as a fungicide. It is used in vineyards, fruit-farms and gardens to prevent infestations of downy mildew, powdery mildew and other fungi. It is sprayed on plants as a preventive treatment; its mode of action is ineffective after a fungus has become established.
It was invented in the Bordeaux region of France in the late 19th century. Hear this story in this video.
If it is applied in large quantities annually for many years, the copper in the mixture eventually becomes a pollutant.
Epsom salt is a magnesium sulfate compound, unlike sodium table salt. Epsom salt has been used for hundreds of years as a healing agent and pain reliever. Today, it’s most often added to hot baths and foot soaks to reduce stress.
Why is it called Epsom salt? Find out from this video.
Nails are most commonly used to fasten pieces of wood together, but they are also used with plastic, drywall, masonry, and concrete. Nails are usually made of steel but can also be made of stainless steel, iron, copper, aluminium, or bronze.
In this video, you can hear the story of how, in 17th century, an English ironmaster from a small town in England recaptured preeminent position of his town for making and supplying iron nails at a low cost!
Richard Foley (1580–1657) was a prominent English ironmaster. He is best known from the folktale of “Fiddler Foley”. Richard himself is likely to have traded in nails rather than making them. In the 1620s, he became a partner in a network of ironworks in south Staffordshire, which were undoubtedly the source of the family’s fortune. According to the folktale, he went to Sweden where, posing as a simple fiddler, he succeeded in discovering the secret of the slitting mill, which was enabling the price of English nails to be undercut. He returned home and set up a slitting mill at Hyde Mill in Kinver, thus making his fortune.
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