Mechanical Universe Flashcards
(41 cards)
What were the first inventions used to tell time? By which civilization? Which was more accurate.
Sundials and water clocks, Mesopotamia c. 3500 BC. Water clock more accurate.
What was a benefit of sundials as opposed to water clocks?
Portability.
What were disadvantages to water clocks?
Not portable, would freeze.
Who invented the candle clock?
China.
What was a benefit of the candle clock? Disadvantages?
Works indoors and at night.
Not so portable, expensive, would start fires.
How did a candle clock work?
Candles were calibrated, divided into hours, hours would burn the stick down with candle flame.
Which clock mechanism was used as the first alarm clock? Who was this commonly used by?
Candle clock, monks.
What were advantages and disadvantages of sand clocks?
Accurate for short periods of time, but not for long (flipping required).
Hourglasses were expensive, only glass makers in Florence could produce it.
What is the greatest invention along with the plow and printing press?
The mechanical clock.
What was the Abul-Abbas clock?
A clock put together by Islamic scholars, with credit given to Archimedes. Mounted on a white elephant, made it special. First cuckoo clock, mechanical bird would signify every hour passing by.
What was the Su Song clock?
Most complex mechanical computer of its time, similar to Archimedes’ design, Chinese.
Where does the word clock come from?
Clocka, latin, means bell.
Who created the first mechanical clock with an alarm? Why?
Richard of Wallingford, to wake monks up with a bell early in the morning to pray.
What is the Astrarium?
Giovanni de’Dondi’s mechanical computer of 1364. Most complex computer of its time.
Contained motions of all planets, calendars.
Why was the Astrarium so important?
Universe was represented as a machine for the first time in a medieval context, led to scientific revolution.
Who was John Harrison?
A carpenter in the 18th century who created a series of accurate clocks.
What was the prize John Harrison had a lifelong dream of competing for?
The longitude prize.
What level of accuracy was required to measure time for figuring out the longitudes of travel?
1 s/day.
What level of accuracy is attributed to modern watches?
6 s/day.
In the time of John Harrison, what was the level of accuracy for a typical clock?
1-20 mins/day on land.
What were the series of clocks that Harrison made called?
Harrison H1 - H5.
What is the story of John Harrison’s applying his clocks to the committee for the longitude prize?
Submitted H1 and the committee asked him why he, a carpenter was doing this? Gave him some money, told him to go build a chair, tells him they’ll tell him of the results soon. In meantime he built H2, and reapplied, same thing happened. Same thing happened all the way to H4. Did not get any results back until then.
What was different about the H4?
It was a watch.
How was the accuracy of the H4 confirmed?
They gave it to James Cook he confirmed it on his explorations.
