A  serious  loss  of  head  always  occurs  when  water  passes  through
a  narrow  opening  from  one  chamber  to  another.  The  defects
of  this  arrangement  are  similar  to  what  would  be  met  with  in
attempting  to  regulate  the  supph-  of  water  to  a  turbine  by  a
throttle-gate  in  the  penstock.
There  are  other  forms  of  turbine  which  tlie  writer  would  be
glad  to  describe  and  consider  if  he  could  obtain  the  necessary
data.  Prominent  among  these  is  the  Leffel  wheel,  made  at
Springfield,  Ohio,  which  has  met  with  extended  application  in
the  Western  States  and  is  not  unknown  in  the  I'Lastern  section,
which  facts  entitle  us  to  presume  that  it  has  points  of  merit.
But  nothing  can  be  learned  from  the  numerous  publications  of
the  makers  as  to  the  constructicni  of  the  wheel  or  the  manner
in  which  the  water  acts  to  propel  it.  Equally  reticent  are  the
makers  as  to  the  efficiency  of  the  wheel.  They  do  not  believe
in  tests  and  assume  that  their  readers  attach  no  importance  to
tliem.  Their  publications  abound  in  vociferous  assurances  of
the  excellence   of  the  \Vheel,    but  neither  give  the   intending


332  TURBINES.
purchaser  the  means  of  judging-  for  himself  nor  furnish  him  with
the  results  of  exact  experiments  as  to  its  performance.
The  Hercules  Wheel,  so  called,  made  by  the  Holyoke
Machine  Company  at  Holyoke,  Mass.,  is  very  extensively  used
in  New  England  and  the  Middle  States.  The  makers  issue  a
very  neat  catalogue  giving  illustrations  and  description  of  all
the  appurtenances  and  attachments  of  the  wheel,  but  the
inquiring  reader  will  search  it  in  \^ain  for  any  information  as  to
the  construction  of  the  wheel,  the  forms  of  the  floats  and
guides,  the  regulation  of  the  water,  or  its  mode  of  action.
