The  late  C.  E.  Amos,  C.E. 
267 
showed  that  some  of  these  driven  bj  four  horses  required  three- 
horse-power  to  drive  them  when  empty,  thus  accomplishing  but 
25  per  cent,  of  real  work. 
At  the  Lincoln  Show,  in  1854,  he  introduced  a rotary  Dyna- 
mometer to  indicate  the  power  consumed  by  any  machine 
driven  by  steam — practically  recording  the  varying  stress  on  the 
driving-belt  from  the  steam-engine  or  other  prime  mover. 
This  was  used  in  the  trials  of  Fowler’s  four-furrow  steam- 
plough,  and  on  the  early  forms  of  steam-ploughing  apparatus  ; 
but  most  notably  at  the  great  experiments  in  steam-ploughing 
on  the  land  of  the  late  Mr.  Fisher  Hobbs,  at  Boxted  Lodge,  in 
connection  with  the  Society’s  Chelmsford  Meeting  of  1856.  The 
arrangement  of  this  apparatus  has  thus  been  shortly  described 
by  his  son,  Mr.  James  C.  Amos,  who  took  an  active  part, 
assisting  in  these  the  first  important  recorded  trials  of  steam- 
cultivation  : — “ The  special  arrangement  adopted,  viz.,  a double 
windlass  working  a hauling-rope  over  transversing  anchors, 
enabled  the  Dynamometer  to  be  placed  between  the  windlass 
itself  and  the  engine.” 
The  above  experiments  seem  to  form  a marked  epoch  in  the 
progress  of  steam-ploughing,  and  attracted  much  attention  not 
only  in  this,  but  in  other  countries.  I retain  pleasing  recol- 
lections of  this  occasion,  and  of  assisting  in  both  timing  the 
experiments  and  in  checking  the  calculations,  duties  which 
were  rendered  doubly  agreeable  by  the  interest  which  Mr.  Amos 
evinced  in  obtaining  the  final  result. 
At  this  same  Meeting  Mr.  Amos  brought  out  an  adaptation 
of  Bentall’s  Dynamometer  for  ascertaining  the  power  consumed 
by  horse-ploughs,  the  alteration  being  a fresh  arrangement, 
making  the  working  parts  much  more  simple,  thus  diminishing 
the  chances  of  error. 
For  the  Newcastle  Show,  in  1864,  a Dynamometer  was  con- 
structed to  test  the  draught  of  steam-ploughs,  cultivators,  and 
similar  implements.  By  this  the  actual  stress  on  the  steel-wire 
rope  was  recorded.  This  was  an  important  machine,  and  was 
described  by  Mr.  Amos  himself  in  the  Society’s  ‘Journal’ 
(vol.  i.  New  Series,  p.  204).  In  addition  to  the  foregoing,  some 
minor  apparatus  were  arranged  by  him  for  the  Society,  to  mark 
the  stress  on  plough-anchors  and  for  other  purposes. 
From  the  foregoing  brief  summary  it  must  be  evident  that 
both  the  agricultural  and  engineering  world  would  have  been 
much  indebted  to  Mr.  Amos’s  talents  if  they  had  been  devoted 
to  Dynamometers  alone  ; but  he  stopped  not  here,  for  his  inven- 
tions embraced  other  branches  of  engineering  and  mechanics. 
The  idea  of  the  double-engine  system  of  steam-ploughing 
appears  to  have  originated  in  Mr.  Amos’s  mind  ; for  he  had 
