A heat engine
The word "engine" derives from Old French engin, from the Latin ingenium?the root of the word ingenious. Pre-industrial weapons of war, such as catapults, trebuchets and battering rams, were called "siege engines", and knowledge of how to construct them was often treated as a military secret. The word "gin", as in "cotton gin", is short for "engine". Most mechanical devices invented during the industrial revolution were described as engines?the steam engine being a notable example. However, the original steam engines, such as those by Thomas Savery, were not mechanical engines but pumps. In this manner, a fire engine in its original form was merely a water pump, with the engine being transported to the fire by horses.
In modern usage, the term engine typically describes devices, like steam engines and internal combustion engines, that burn or otherwise consume fuel to perform mechanical work by exerting a torque or linear force (usually in the form of thrust). Examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts. Examples of engines which produce thrust include turbofans and rockets.
When the internal combustion engine was invented, the term "motor" was initially used to distinguish it from the steam engine?which was in wide use at the time, powering locomotives and other vehicles such as steam rollers. "Motor" and "engine" later came to be used interchangeably in casual discourse. However, technically, the two words have different meanings. An engine is a device that burns or otherwise consumes fuel, changing its chemical composition, whereas a motor is a device driven by electricity, air, or hydraulic pressure, which does not change the chemical composition of its energy source.3 However, rocketry uses the term rocket motor, even though they consume fuel.
A heat engine may also serve as a prime mover?a component that transforms the flow or changes in pressure of a fluid into mechanical energy.4 An automobile powered by an internal combustion engine may make use of various motors and pumps, but ultimately all such devices derive their power from the engine. Another way of looking at it is that a motor receives power from an external source, and then converts it into mechanical energy, while an engine creates power from pressure (derived directly from the explosive force of combustion or other chemical reaction, or secondarily from the action of some such force on other substances such as air, water, or steam).5
Devices converting heat energy into motion are commonly referred to simply as engines.6
History of oil
On September 6, 1866 American John Ellis founded the Continuous Oil Refining Company (Later to become Valvoline). While studying the possible healing powers of crude oil, Dr. Ellis was disappointed to find no real medicinal value, but was intrigued by its potential lubricating properties. He eventually abandoned the medical practice to devote his time to the development of an all-petroleum, high viscosity lubricant for steam engines ? then using inefficient combinations of petroleum and animal and vegetable fats. He made his breakthrough when he developed an oil that worked effectively in high temperatures. This meant no more gummed valves, corroded cylinders or leaking seals. In 1873 Ellis officially renamed the company to Valvoline after the steam engine valves the product lubricated.
Allowing buses to carry passengers takes place after checking their technical condition. Inspection of road traffic requires that all vehicles that are to serve as vehicles for collective are fully operational and ensure the safety of passengers. Servicing buses should take place after the establishment of any problems with the vehicle, which can occur while driving or be determined at a standstill. Due to the fact that in Poland passenger transport by buses organized frequently by private carriers, who must themselves cover the costs of buying new vehicles, they try to take care of their vehicles so that they can ride as long as possible. One way to prolong the life of vehicles is a frequent replacement of engine oil.