322 Review of Prof. Johnson’s Report on American Coals. 
Synoptical Table, (continued.) 
Cotnbustion: Action of fi : race during steady 
ressure. Evaporation. 
Mean ea Pressure, pl hour 
in hours. 
Designation of 
coals, 
porating one cubic foot 
of water. 
steady action. 
chimney. 
of water. 
atired to bring boiler to 
y action, 
ospheres, above a 
vacuum. 
oa pounds per square inch, 
In pounds. 
of steam in boiler. 
€ 
reaching grate. 
stea 
ce oak ae uring steuly action. 
| In atm 
ounds per a gr ft. of grate sur- 
Of gases, on arriving at 
above | atmosphere. 
Pounds supplied per hour, during 
¥ 
fa 
Gained by the air, before » 
n pounds per sq. foot of ab-|5 
sorbing surface of boiler. 
Time r 
p Deaucht-eange—helght in inches, 
Of air, on arriving at grate. 
; ‘er eva 
Of escaping gases above that 
are 
y 
(<7) 
Sxl! 
p+ 
3& 
g 
t= 
~ 
8 
mw 
S 
Re 
<3 ch 
@ 
2 
fates 
ce 
Oo 
a 
ie 
BE 
~ 
_ 
ae 
: | 
tec) 
—— 
= 
gf 
7 ww 
A.EI9 
haft) average coal,|5417 0-367 {1383/1421 7") 
° 
+ + |3769-63|120-94|8°595|8:445|276-49|337-89) 196- aie. ‘14/0318 
val lover Hill, - + |3775°10| 89°56|/5'843)9°340/362-51|302-54/297-95) 74°81/0°145 
4 hesterfield Minin 
ny, - - |3876 00/119-02 pe ae 252°01/344-58 ae ae. ae 
04 
«eS 
8°756/247°72 boi Ree 
canoe, 302715 86) 72 
306°39 86 be $3 15. 
\ Eee) screened, 7132-00 ee He 8" 7) 285° 2 297°78)216-95 70° 
an. y 
yard,) + = + |1463°50) - « - - - 
PEE 
3 oe Cee i 
Synoptical Table, ( continued.) 
, Lead reduc’ 
Evaporation. Residue from furnace. frm een 
Designation of coals. 
from 212°. 
One cubic foot of Pm 
temperature. 
2 
from 212°, 
ter, from 212°, 
cent. 
tion, per cent. 
100 of fuel, 
each trial. 
pe of clinker and ashes, from 
Ratio of clinker to total waste. 
By one of combustible matter. 
One of fuel, from initial 
One of combustible mat-|* 
= economy of fuel, per 
On rapidity of evapora- 
lone of fuel 
Barr’s p Run 
gaaly & ‘fies ad's 
warring (900 feet shat) a av- 
— pe 
ompany’s coal, - « 
rn hover a, bg 
esterfiel Mi n C 
Midlothian, a ning ompany, 
lctinker alone, from 100 of fuel. 
=\Pounds of unburnt coke, after 
+|By one of fuel. 
8 af 
10142 — 5-056'— 
9:740 + 2-990|— 
pee 
ea ea 
2 
3 
& BS 
ge 
c1@ 
a, 
Ba 
ss 
Se 
WBeSses E 
= 
3 
55 
i 
2 
10° 
ube a 
zoe 
=8 
rele 
Q 9-300 G10 Deo 
-_ 
sas 
ga28 3 
Oo hs 
rs) 
WISI ISI TS 
i=) 
os 
i] 
— 
Ks 
Midiothian, ‘new shaft,” 
“Mid! lothian, Screened, n° = 
Midlothian, (navy yeti ie, “a 
Hy 
i} 
Four of these synoptical tables will be found in the Report. 
Prof. Johnson having in these experiments the most satisfactory 
means of determining the practical heating power of coal, was le 
to inquire whether the celebrated process of Berthier, by the re- 
duction of litharge, could be depended upon as a means of deter- 
