I learned this today. Paper tissues have been used for 1500 years in China, but the modern tissue was invented in 1924. Paper was invented in China in about 100 BC. A government official called Ts’ai Lun is credited as the person who started the paper-making industry. His paper was made by mixing finely chopped […]
#194 When did people start using tissues? Read More »
I learned this today. Glass and metal can be recycled indefinitely, but plastic can only be recycled once or twice and paper about 7 times. Recycling has been around for as long as people have used resources. There is archaeological evidence of scrap bronze being collected and melted down again in Europe. In 1031, a
#193 How many times can you recycle something? Read More »
I learned this today. A pearl forms in the shell of a mollusk when an irritant becomes trapped there and the mollusk covers it with a fluid that hardens. There are three different types of pearl. There are natural pearls, cultured pearls, and imitation pearls. I am not going to look at imitation pearls. Natural
#192 How does a pearl form? Read More »
I learned this today. Maslow’s hierarchy of needs is a universal classification system which has the most important needs at the bottom and then the following needs in an ascending order of importance. Maslow was an American psychologist. He worked from the early 1930s until his death in 1970. He published his hierarchy of needs
#191 What is Maslow’s Hierarchy of Needs? Read More »
I learned this today. Nobody actually knows what the core of Jupiter is like. The most predominant theory is that it has a rocky core surrounded by a layer of metallic hydrogen. Jupiter is the largest planet in the solar system. It is 1,321 the volume of Earth and is a gas giant. It is
#190 What is the core of Jupiter like? Read More »
I learned this today. Our voices change when we inhale helium because sound travels through it faster than it does through air. There are two things we need to look at: Why sound travels at different speeds through different mediums and how our voices work. Sound is a wave of vibrations that travel through a
#189 Why does our voice change when we inhale helium? Read More »
I learned this today. The Teapot Dome scandal had nothing to do with tea or teapots. It was the biggest scandal in America before Watergate. It all started when the US Navy started to convert its ships from coal power to oil power in 1909. They needed a reliable supply of oil and President Taft
#188 What was the Teapot Dome scandal? Read More »
I learned this today. It is possible to make a new element, but it is not easy, takes a lot of power, and the resultant element would not be very stable. There are 118 known elements that appear on the periodic table. The first 94 of them occur naturally on Earth and the other 24
#187 Is it possible to make a new element? Read More »
I learned this today. Vellum is a material for writing on that is made from prepared animal skin. The document on the front of this article is the Magna Carta. It is the document that tried to control King John of England and is one of the most famous documents in the UK. It was
#186 What is vellum? Read More »
I learned this today. The California Gold Rush started when James Wilson Marshall found gold flakes in the American River at the base of the Sierra Nevada Mountains near Coloma in California on January 24th, 1848. California was governed by Mexico after it gained independence from Spain in 1821. The area was remote and sparsely
#185 What started the California Gold Rush? Read More »
