KELATIVE  FUEL-VALUE  OF   ALCOHOL  AND  WOOD-SPIRIT.  265 
the  color  became  darker  on  the  addition  of  caustic  soda  or 
sulphuric  acid. 
The  alcohol  had  a  density  of  0-845. 
The  apparatus  employed  for  these  experiments  consisted  of  a 
lamp  for  the  combustion  of  the  spirit,  the  burner  being  surrounded 
by  a  cylinder  eight  inches  in  diameter,  and  a  light  brass  pan 
supported  above  the  flame  for  holding  the  water  to  be  evaporated. 
Each  experiment  extended  over  about  two  hours.  In  each,  the 
true  quantity  of  water  evaporated  and  quantity  of  spirit  burnt  were 
observed.  The  quantity  of  water,  at  212°  F.,  remaining  in  the 
pan  was  likewise  observed,  the  quantity  of  steam  that  would  have 
been  produced  by  the  heat  thus  consumed  calculated,  and  added 
to  the  quantity  of  water  evaporated.  One  fraction  of  the  effect 
— the  heat  consumed  in  raising  the  water  from  62°  to  212°  F. 
— is  not  included  in  the  table  below  : — 
A.  B. 
Consumption  Evaporation  Ratio  Duration  of 
of  fuel  in  of  water  in  of  experiment 
grammes.          grammes.  B  to  A.  in  minutes. 
(  1.        98             51-1°  5-25  101 
w    ,       'J  2.       133  697  5-25  149 
Wood-spirit^  3        124  59T  4.gl  13g 
1 4.       198  782  3-95  165 
160  580  4-25  104 
178  781  4-38  148 
133  590  4-43  119 
159  687  4-32  170 
In  the  experiments  1,  2,  3  and  6,  7,  8,  the  distance  between 
the  bottom  of  the  pan  and  the  level  of  the  wick  was  always  the 
same.  In  order  to  ascertain  the  influence  of  the  greater  eleva- 
tion of  the  pan,  it  was  raised  in  experiments  4  and  5  about  three- 
quarters  of  an  inch  further  from  the  flame.  The  result  showed 
a  loss  in  this  case. 
According  to  the  first  three  and  last  three  data,  the  heating 
capabilities  of  alcohol  and  wood-spirit  are  as  43  :  50,  or  nearly 
6  :  7.  The  prices  however  were  as  8  :  6  ;  consequent^  the  cost 
of  evaporating  a  given  quantity  of  water  by  means  of  alcohol 
would  amount  to  56,  while  with  wood-spirit  it  would  be  only  36  ; 
or  wood-spirit,  under  such  circumstance,  would  be  nine-four- 
teenths cheaper  fuel  than  alcohol. — Chemical  G-azette,  February, 
1855,  from  Schweizerisches  Gewerbeblatt,  June  1854. 
Alcohol 
