Source : Webster's Revised Unabridged Dictionary (1913)

Turbine \Tur"bine\, n.
   A form of steam engine analogous in construction and action
   to the water turbine. There are practically only two distinct
   kinds, and they are typified in the de Laval and the Parsons
   and Curtis turbines. The

   {de Laval turbine} is an impulse turbine, in which steam
      impinges upon revolving blades from a flared nozzle. The
      flare of the nozzle causes expansion of the steam, and
      hence changes its pressure energy into kinetic energy. An
      enormous velocity (30,000 revolutions per minute in the 5
      H. P. size) is requisite for high efficiency, and the
      machine has therefore to be geared down to be of practical
      use. Some recent development of this type include turbines
      formed of several de Laval elements compounded as in the
      ordinary expansion engine. The

   {Parsons turbine} is an impulse-and-reaction turbine, usually
      of the axial type. The steam is constrained to pass
      successively through alternate rows of fixed and moving
      blades, being expanded down to a condenser pressure of
      about 1 lb. per square inch absolute. The

   {Curtis turbine} is somewhat simpler than the Parsons, and
      consists of elements each of which has at least two rows
      of moving blades and one row of stationary. The bucket
      velocity is lowered by fractional velocity reduction. Both
      the Parsons and Curtis turbines are suitable for driving
      dynamos and steamships directly. In efficiency, lightness,
      and bulk for a given power, they compare favorably with
      reciprocating engines.