Heliocentric Theory 

The ptolemaic model believed the heavens revolved around the Earth. Aristotle believed the stars and plants were divine moving in perfect circles. Ptolemy had to modify Aristotle’s ideal model to match observations. Ptolemy’s was founded upon Aristotle’s faith. It was physically wrong but accurately predicted orbits. Moslim scholars began criticizing ptolem’s models. Nicholaus copernicus devised the heliocentric theory by 1543. The heliocentric theory was accurate in its  predictions AND physically correct. It revealed the actual structure of the solar system. Space exploration requires exact knowledge of planetary positions. The theory of copernicus was slow to catch on.

Nicholas Copernicus

Nicholas Copernicus was born in Poland in 1473. Copericus developed an interest in astronomy in school. He grew fascinated by the contradictions between Aristotle and Ptolem’s model. At Bologna he observed discrepancies with the model. His theory’s first draft was completed in 1514. His insight didn’t come from Renaissance literature. Cpernicus christen faith provided the basis for the scientific revolution. He believed science was possible because God sustains the universe. He thought a more simple design was the sun at the center. He also made numerous other measurements and astronomical discoveries. He had diverse interests but specialized in astronomy. 

Andreas Veralius 

    

Andreas Vernalius was born in 1514 in Brussels. His father, grandfather, and great grandfather were doctors for the German emperor. He began college in the Netherlands but moved to Paris and became interested in anatomy. He learned of Galen and his critics. A major insight: Galen’s knowledge based on animals not people. No one had checked Galen’s work in 1300 years. Vesalius published a crucial treatise on anatomy in 1543. It gives detailed descriptions of the entire human body. Vesalius innovated: he did what doctors before him thought was beneath them. He provided critical and conductive criticism of anatomical knowledge.

Pencil 

Writing instruments go back to the dawn of mankind. The Romans used an “erasable” wax tablet. Erasable tablets were cheaper than ink and parchment. A large graphite mine was discovered in England. The wooden encasement was developed in 1560 and the modern pencil-making techniques arose by 1600. Pencils are graphite rods eneuced in wood. Pencils make durable markings. They are cheap to make and use. Pencils offer benefits to artists. Artists immediately grasped the benefits of the pencil. The use of graphite in making cannonballs gave the English military advantages. King Henry VII took control over the mine and revicted access. England gained a world monopoly on pencil making.           

Mariner’s Astrolabe

  The interest in sailing prompted the design of better instruments like the cross staff helped determine latitude but it had drawbacks. The quadrant was also used but was too sensitive. The portuguese founded nautical schools dedicated to sailing in the early 15th century. Those schools led to developments in sailing instruments. The mariner’s astrolabe addressed two problems: ocean motion and wind. It is made of heavy brass with slots cut in its center. It was a two-handed instrument used to read angles above the horizon. It was combined with ancient star charts to determine latitude. 

Double-Entry Bookkeeping

The Romans had sophisticated accounting techniques. Europe slowly recovered after Romans had sophisticated accounting techniques. Europe slowly recovered after Rome’s collapse. Italy recovered faster due to its closeness to the Pope. As the merchant economies became money-based and accelerated more sophisticated methods were needed. Double-entry bookkeeping enters each transaction. Double-entry bookkeeping keeps everything balanced. Two entries must be made for everyone tradsction. Being the victim of theft reduces your equity. Luca Pacioli’s book was a commercial success within the merchant class. Double-entry bookkeeping protects you from theft. It raises the price to steal from a shrewd business. Most criminals are stuped and can’t defeat the system. Its benefits increase your wealth and protect you from theft.

Luca Pacioli 

Luca pacioli gained an interest in math and arithmetic from an early age. He moved to Venice when he was 20. He became a friar when he was about 30. Luca taught math and arithmetic at numerous universities. He returned to his hometown just before he turned 50 and wrote his most famous book. Luca’s most famous book is a practical business handbook. It wasn’t original except in how it compiled all the knowledge of the day. He wrote about the application of math and geometry to art and architure. He wrote about chess with illustrations by Leonardo da vinci. Pacioli was invited to milan in 1496 where he met Leonardo da vinci. Pacioli moved to Florence and taught geometry at the university in 1500. His book benefited from the recently invented printing press. He wrote clearly which made his books popular. Pecioli’s biggest impact is the popularization of double-entry accounting. He made mistakes but they led to further discoveries. 

Leonado da Vinci

Leonardo was the son of a rich government official and had 12 siblings. He received an informal education in Latin, geometry,and math as a child . He apprenticed under a master painter in Florence when he was 14. He was a master painter by the time he was 20. He was being paid to paint by his late 20’s. He was a naturally gifted child who couldn’t focus. He drew a lot and paid attention to the details. He became a military engineer. He understood mechanics and drew detailed designs for inventions. His most famous works are The Mona Lisa and the Last Supper. He gained early renown for collaborating on The Baptism of Christ. He was supported by the Duke of Milan through 1499. He was supported by the king of France after 1562. Da Vinci is described as a “Renaissance Man”. A renaissance man is supposed to have diverse Knowledge and skills. Da Vinci was a talented artist but not a good investor. He struggled to finish the projects he started. He is mostly remembered for The Mona Lisa.

 

Chess

Chess originated in India in the 6th century AD. “Check” and “checkmate” were added into the game by the persians. The Muslims changed the pieces into abstract objects instead of people and animals. Under Christan influence the pieces became people and animals once again. Chess teaches military strategy and math skills. Pawns represent standard infantry (foot soldiers), knights are the main attacker, the bishop represents a church clergyman, the rook represents a fortified offensive, the queen is the strongest piece in the game, the king is the most important piece. Chess is full of possible strategies especially thanks to promotion Chess spread to Europe by the Muslims through Spain and the Byzantine Empire. It spread because of its social and military value.  

Arquebus 

The arquebus began as the hand cannon in China in the 13th century. They were simple, a barrel and a handle, and a series of innovations improved the hand cannon. Early versions weren’t effective long-range weapons; stronger guns were needed by the 15th century to penetrate plate armor. The arquebus is the ancestor of the musket and rifle. Its accuracy was greatly improved over previous efforts It was also much more powerful than the hand cannons. It made warfare cheaper. The king of Hungary was the first to heavily stock his army. 25% of his army carried an arquebus. It was quicker to train soldiers to fire than to learn archery. 

Printing Press

China invented woodblock printing in the 700s AD. Movable type was in Asia by the 1200s AD. By the 1400s, Europe had paper and high labor costs associated with scribes. Johan Gutenberg applied his knowledge of metalworking to invent the printing press. It is the single most important invention faster and cheaper in the last l,000 years. Books could now be printed faster and cheaper. 3,600 pages a day could be printed and about 10 books. It had little impact in Asia. The printing press spread rapidly throughout Europe. 

Mainspring 

English Longbow

The English longbow was as tall as it’s archer. It required a lot of strength and skill to wield the English longbow. In order to have the strength and skill to wield the longbow training began when the archers were young boys and as the boys grew so did their longbow to match their height. The English longbow fired 300 yards 6 arrows per minute. The arrows could penetrate armor.  Demand for wood to make the longbow depleted forests all over continental Europe. England purchased over 12 million arrows for their bows in 18 years. English laws were passed making archery practice mandatory. Then Guns began replacing the bow by the 1600s.

Blast Furnace

The earliest blast furnaces were probably developed in China 2,000 years ago but they didn’t spread in adoption. The first big advance in bloomery design occurred in Spain in the 700s AD. Iron that got too hot in a bloomery turned into pig iron which was hard to refine. Water-powered bellows helped force enormous air volume into the bloomeries which made them very hot. The  first blast furnaces appeared in Switzerland and Sweden around 1300 AD. The blast furnace converts iron ore pig iron effently.     

Plate Armor

Chain mail had been around for centuries and was an effective defense against medieval weapons but it was expensive and labor intensive to make. But then a coat of metal plates evolved during the 1200s it was gradually refined to become more form-fitting and to cover more parts of the body. The first suits of plate armor were developed by 1420 AD. It protected the knight from most kinds of attacks, even arrows. Plate armor was light and flexible so the knights could run, jump and pretty much do what they can do without the armor. It’s use declined in the 1600s. 

   Spurs 

No one knows when the spur was invented. Early versions were worn by the Greeks and Romans. The spur began to take on its modern form in England in the 13th century. It arose out of a desire to better communicate with your horse. Improves rider’s control over the horse. It increases the horse’s sensitivity to leg commands.

The Most Interesting Thing I Learned About This Week 

The most interesting thing I learned about this week is the spur because I got to learn a little bit more about the history of the spur because I use spurs all the time.

So this is a rowel spur I have at my house.

  This is my mom old barrel racing spur which is a lighter version of the spur it is a bumper spur.

     

Spectacles

 Old age was a threat to  the division of labor by putting people into premature retirement for bad vision. Old age was also frightening for scholars because monks and scholars made their livings based on their studies. The lens as a magnifying tool has been known since ancient times. A gradual increase in vision led to the first eyeglasses. Eyeglasses thwart the effects of old age on our vision. Robert Grosseteste a christain scholar made advances in studying the nature of light. 

Mechanical Clocks 

Life was much less orderly and regulated before the mechanical clock. By the 1200s a variety of tools were available for telling time there was the sundial, water clocks, and the hourglass. Water clocks were good but they froze in cold weather. The clock enables us to track much smaller time intervals than before. The hours of the day varied in length before the clock. Clocks began to regulate prayer time and the calendar. 

Paper Mills

The recipe and the paper-making process were known in Europe. The main ingredient was old linen rags. The spinning wheel increased demand for linen clothing but there was a problem with all the trash  (old linen clothes.) People began taking the old linen clothes and turning them into paper but then they sold it cheaply. 

The most interesting thing I learned this week and why

The most interesting thing I learned this week is the paper mills and how people used old linen rags to make paper.