Lesson 61: Jackhammer
In 1848 there was a strange outbreak of revolutions. A lot of them occurred because of cults.Also because some people believed that violent revolutions healed society. Across the sea America did not have these problems.
Mining was important but dangerous and steam engines were important tools for the process. An early jackhammer was invented in 1809 and a man named Jonathan Couch invented the modern version in 1848 which he called a percussion drill.
The jackhammer is a device for chipping away stone and concrete. The bit attached to a piston that a steam engine would bash into the rock. The bit is pushed up and down by pressurized air. Some run on electricity.
The steam engines could not be installed in the mines they produced to many bad gases. So Couch’s assistant Fowle invented compressed air.
The Mont Cenis tunnel links Italy to France. It was destined to take 25 years to build, as it was built into a mountain. But, thanks to the jackhammer it only took 14 years. The jackhammer can be used by homeowners and helps speed up road construction.
Lesson 62: Pin Tumbler Lock
Linus Yale Sr. was born in Connecticut in 1797. He moved to New York, married his wife at age 18 and had 4 children. He opened a lock shop to sell bank locks and invented the pin tumbler lock in 1843 to use in safes.
It was first called a Yale Lock and was a cylinder drum. The key lined up with the pins, pushed some up and some down, and then opened the lock. It was hard to know the length of the pins so harder to pick.
Linus Yale Jr. continued his father’s industry after he died. He became an electrical engineer and the lock became popular. Linus Jr. took the invention to the World’s Fair and advertised its benefits. He also exposed the easy picking of other locks.
The pin tumbler lock is used in the common door and new feature enhanced security adjustments are always being made. Its safety guarantees helped people trust banks for keeping their money safe. This led to the banking industry to becoming the most elite industry today.
Lesson 63: Safety Pin
The Irish Potato Famine drove immigration to America. It all started with a potato blight in the 1840s and two thirds of the population (that relied on potatoes because of outrageous Corn Laws) went hungry and immigrated to America. So 1 million people died and 1 million immigrated.
Walter Hunt was born in New York in 1797. Not much is known about him except that he became a mechanic and had an eye for invention. He invented version of the sewing machine and had experience with needles. He invented the safety pin in 1849 to pay back a debt.
Safety pins are simple folding needles. They have sharp heads and guards to keep the pins from sticking you. Sewing pins wiggled free and pricked you, these did not.
Hunt invented the safety pin to pay back a debt of 15 dollars. He sold his patent for 400 dollars to a company named WR Grace and company. Grace was the last name of the man who founded the company, an immigrant from the Irish potato famine. 15$ then is equal to 450$ today and 400$ to 12,000$. The company advertised to house wives and nurses for diapers and clothes.
Today they are still used in diapers and they helped reduce household expenses.
Lesson 64: Gyroscopes
France had a long 19th century. Napoleon was overthrown in 1814, the Bourbon Dynasty was overthrown in 1830 and the socialist overthrow happened in 1848. Then, Napoleon the 3rd took over in 1852.
Leon Foucault was born in Paris in 1819. He was home-schooled and went to medical school to become a doctor but was afraid of blood. He became interested in physics and became apprenticed to the man who discovered Leukemia. He then worked with a man and helped discover the speed of light. In 1851 he experimented with the earth’s rotation and then invented gyroscopes in 1852.
The gyroscope is a spinning disc inside gimbals. The word gyroscope is a combination of two Greek words that mean “circle” and “to look”. They seem to defy the laws of physics but they don’t. the gimbals allow the rotation and they resist forces that try to turn them. The gyros create stability.
Foucault used the gyroscope to prove the earth’s rotation and electrical motors were added in the1860s. The compass used gyroscopes in 1904 and they were used for military aircraft in World War 1 and World War 2.
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