Tamp — To  pack  with  earth  or  other  materials.
Target — An  instrument  used  as  a  flag  in  directing  surveyors.
Terreplein — The  level  fill  or  surface  of  earth  made  to  connect

with  flumes,  etc.
Tumbeam — A  sort  of  treadmill  device  used  in  Oriental  lands

for  raising  water.
Tympanum — A  large  drum-wheel  for  raising  water  from  a  run-
ning stream.
Underflow — Currents  of  water  below  the  earth's  surface.
Warping — A  method   of  retaining  water  by  means  of  banks  in

overflows,  as  of  tides  along  the  ocean  shore.
Waste  Gate — An  outlet  for  discharging  water  from  a  canal  or

storage  pond.
Water  Register — An    instrument    for    measuring   the  flow   of

streams.
Water  Right — A  privilege  ;  the  right  to  the  possession  and  use

of  water  for  irrigating.
Water  Witchery — Art  of  discovering  the  underground  presence

of  water  by  aid  of  divining  rods.
490  IRRIGATION   FARMING.
Weir — A  sort  of  dam  placed  in  a  stream  for  diverting  or  meas
uring  water.
Well — A  source  of  water-supply;  a  hollow  tower  in  a  reser-
voir

Wind  Rustler— A   crude  apparatus  serving  the  purpose  of  a
windmill.
Wind  Dam — A  jetty  or  barrier  built  into  a  stream  to  deflect
the  current.
Zanjero — Spanish  term  for  a  ditch-walker  or  overseer.
