Hourglass - a water clock, in later times as sand, consisting of two, usually glass tubes, one of which is located exactly above the other, the combined tube passing down the amount of water or sand in the specified time. Are known for measuring hourglass for several seconds to days
The plane - an aircraft heavier than air (aerodyn), continuing in the air thanks to the power generated by fixed carrier, under the circumstances relative to the vessel, the wings. The sequence needed to maintain speed is produced by one or more engines.
There are two types of drives:
propeller, in which the engine torque is converted to a string using the propeller, to such power shall be piston or turbine engines,
jet, in which the sequence is produced directly in the engine, typically used turbojet engines, rocket engines are mainly used in construction of experimental or as auxiliary drive at startup.
mom nadzieje że się przydałem XD