613 
Report  on  Implements  at  York. 
overrated.  Such  a machine  was  used  during  last  autumn  and 
winter  in  removing  obstructions  from  the  small  streams  near 
Minety,  on  the  borders  of  Gloucestershire  and  Wiltshire,  which 
constitute  some  of  the  sources  of  the  Thames.  The  valleys 
in  contiguity  with  these 
streams  had  suffered  se- 
verely from  floodings  for 
some  years  ; but  so  effec- 
tive was  the  work,  and 
such  the  amount  of  deposit 
removed,  that  not  a single 
flood  has  occurred  since  the 
work  was  done.  One  great 
merit  of  the  Dredger  is 
that,  worked  either  from 
the  bank  or  from  a barge, 
according  to  the  size  of  the 
stream,  it  not  only  removes 
the  mud,  but  deposits  it  on 
the  bank,  and  thus  a double 
operation  is  performed — 
the  river-bed  is  cleaned, 
and  the  banks  are  raised 
simultaneously. 
The  drawings  represent 
side  and  end  views  of  one 
of  these  dredgers  on  strong 
bogie  frame,  as  it  would  be 
worked  Irom  the  bank,  and 
moved  forwards  as  the  work 
proceeds ; but  it  can  be 
equally  well  fixed  on  a 
narrow  barge. 
The  weight  of  the  ma- 
chine is  90  cwts.,  cost  price, 
2951.  It  is  carried  on  a 
strong  wooden  bogie  on 
four  wrought-iron  wheels, 
9 inches  broad,  for  travel- 
ling over  soft  land,  fitted 
with  two  cylinders,  4 inches 
diameter  by  7 inches  stroke, 
with  all  the  necessary  gear- 
ing for  lifting,  lowering, 
or  grab  upon  a jib,  making 
pillar.  The  boiler  is  of 
ig.  13. — End  view  of  Priesiman's 
Dredger. 
and  turning  round  the  bucket 
a radius  of  13  feet  from  the  centre 
the  ordinary  vertical  cross-tube 
