The combine harvester it was an upgrade from the mechanical reaper kind of, the combine harvester was made for crops and to harvest. It will be a very large machine to have blades in the front cutting it, then a drop shoot will appear there and collect it in the back of the machine. It was made so framers with thousands or even millions of crops could harvest, was also formally made in 1790-1820 until other people used it.
The solar compass was used for tracking the time and locations. It was made in 1792 WIlliam Austin Burt, for romans to use. When it was made people thought it was used for tracking people down which started a war from France and Europe.
The propeller its used for boats its hooked to an engine which starts gears and spins the propeller to go fast. It’s made up of friction and plastic surrounding it the friction stops the water from rusting too quickly. The plastic around stops the water from entering the engine and from electrocuting the machine. We use it every day it used in fans, boats, planes, and more. propeller is a good invention without it we would have no planes or no boats or no generators even.
The mechanical computer it was first used up of circuits and gears with codes it was used for a calculator. Or known a math answer when you type a physical number will show then directly give you the answer it was made in 1791 in London.
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