201 
or  THE  ESSENTIAL  OIL  OF  EUE. 
III.  ‘2047  gramme  gave  '5820  gramme  carbonic  acid  and  ‘2349  water. 
IV.  ‘2212  gramme  gave  •6320  gramme  carbonic  acid  and  ‘2562  water. 
V.  ‘IQSG  gramme  gave  ‘5662  gramme  carbonic  acid  and  *2352  water. 
VI.  ’2138  gramme  gave  '6103  gramme  carbonic  acid  and  •2501  water. 
VII.  ‘2131  gramme  gave  ‘6077  gramme  carbonic  acid  and  ‘2494  water.  • 
VIII.  -2128  gramme  gave  ‘6067  gramme  carbonic  acid  and  ‘2552  water. 
I. 
II. 
Carbon . 
77-65 
77-47 
Hydrogen  . 
13-05 
13-37 
Oxygen 
9-30 
9-16 
100-00 
100-00 
Carbon  . . 
Hydi‘ogen  . 
Oxygen  . 
III. 
77-54 
12-75 
9-71 
IV. 
77-92 
12-87 
9-21 
V. 
77-75 
13-16 
9-09 
100-00 
100-00 
100-00 
Mean. 
. 77-71 
C22 
. 13-07 
H22 
. 9-22 
0^ 
100-00 
VI. 
VII. 
VIII. 
77-85 
77-77 
77-76 
13-00 
13-00 
13-32 
9-15 
9-23 
8-92 
100-00 
100-00 
100-00 
Calculation. 
. ^ ^ 
132  77-65 
22  12-94 
16  9-41 
170  100-00 
The  above  combustions  were  made  in  the  manner  described  in  the  first  part  of  my 
paper  “ On  some  of  the  Products  of  the  Destructive  Distillation  of  Boghead  Coal*.” 
The  annexed  values  were  obtained  in  two  determinations  of  the  density  of  the  vapour. 
In  order  to  pravent  oxidation,  the  balloon  was  in  each  case  filled  with  hydrogen  previous 
to  immersion  in  the  bath. 
I. 
II. 
Temperature  of  the  air  . . 
. . 18° 
16° 
Temperature  of  the  vapour. 
. . 247° 
259° 
Pressure 
. . 760 
759-2  mm. 
Excess  of  weight  of  balloon 
. . -2220 
•5770  gramme. 
Capacity  of  balloon  . . . ’ . 
. . 82-5 
228-0  cub.  cent. 
Residual  hydrogen  .... 
. . 1-0 
10-0  cub.  cent. 
Density  of  vapour  .... 
. . 5-83 
5-91 
The  formula  C^^H^^O^=4  volumes,  requires — 
22  volumes  carbon  vapour  . 
44  volumes  hydrogen 
2 volumes  oxygen 
0-8290.22=18-2380 
0- 0692.44=  3-0448 
1- 1056.  2=  2-2112 
23-4940 
4 
5-8735 
Experiment  (mean). 
5-87 
Theory. 
5-874 
MDCCCLVIII. 
* Philosophical  Transactions,  1857. 
2 E 
