Amaro (Italian for  bitter ) is an Italian herbal liqueur that is commonly drunk as an after-dinner digestif. It usually has a bitter-sweet flavor, sometimes syrupy, and has an alcohol content between 16% and 40%. Similar liqueurs have traditionally been produced throughout Europe.maro should not be confused with amaretto, another Italian liqueur that is sweet and flavored with almonds or with the pits of drupe fruits such as apricots.
An external combustion engine (EC engine) is a heat engine where a working fluid, contained internally, is heated by combustion in an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine, produces motion and usable work.
The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar four-stroke and two-stroke piston engines, along with variants, such as the six-stroke piston engine and the Wankel rotary engine.he very first internal combustion engines did not compress the mixture. The first part of the piston downstroke drew in a fuel-air mixture, then the inlet valve closed and, in the remainder of the down-stroke, the fuel-air mixture fired.