216     ICE  ;  ITS  COLLECTION,  STORAGE  AND  DISTRIBUTION. 
The  hand  plow  comes  next,  as  preceding  all  the  others.  Let 
the  reader  mentally  figure  to  himself  a  plate  of  good,  tough,  well 
tempered  steel,  three  feet  in  length,  four  inches  wide  at  one  end, 
and  five'and  a  half  inches  at  the  other.  The  ends  are  square 
with  the  edge,  which  is  uppermost  when  in  use,  so  that  the  oppo- 
site side  alone  diverges  from  a  right  angle  with  them.  The 
straight  side  is  strengthened  by  two  bars  of  iron  rivetted  on  both 
sides  of  it,  while  the  other  is  cut  into  teeth,  by  slits,  from  one- 
quarter  to  one-half  an  inch  in  width,  inclined  backwards  from 
the  front,  and  extending  entirely  up  to  the  stiffening  bars  above 
mentioned,  so  that,  when  propelled,  the  teeth  present  a  sharp 
edge  to  the  ice  against  which  they  are  pushed,  and  each  tooth 
being  a  quarter  of  an  inch  deeper  than  the  one  which  it  follows, 
cuts  a  groove  corresponding  in  depth,  so  that  the  groove  made  is 
three  and  a  half  inches  in  depth.  To  the  middle  of  the  upper 
edge,  or  what,  in  analogy  with  a  comb,  which  it  somewhat  re- 
sembles, might  be  termed  the  "  back,"  is  attached  the  handle  by 
which  it  is  pushed  forward, — a  stiff  bar  of  iron,  hinged  or  rivet- 
ted, as  the  case  may  be,  at  the  requisite  inclination.  The  lower 
angle  formed  by  the  hinder  tooth  with  the  end  is  usually  trun- 
cated, thus  saving  material  and  weight.  [The  figure  of  the  large 
ice-plow  will  give  an  idea  of  the  hand  plow. — Ed.] 
SWING  GUIDE  MAEKER. 
Next  comes  the  swing  guide  marker.  This  implement  differs 
from  the  hand  plow  in  being  considerably  larger,  having  two 
handles,  similar  to  those  of  the  tools  employed  in  plowing  land, 
set  on  to  the  hinder  end  of  the  plow.  The  swing  guide,  to  which 
it  owes  its  distinctive  appellation,  consists  of  a  plate  of  the  same 
steel  as  forms  the  cutting  part  of  the  plow,  attached  by  two  bars 
to  the  back,  so  that  it  will  run  parallel  with  it  at  twenty-two 
inches  distance  (the  width  of  a  cake  of  ice).    These  bars  are  so 
