FLAME SPECTBA AT HIGH TEMPERATURES. 
1083 
flame by Watts. Finally, we have this striking fact to consider : when slag from the 
converter is ignited at the highest temperature of the oxyhydrogen blowpipe, the red 
potassium, the red lithium, and the yellow sodium lines are present exactly as they 
are seen in the Bessemer-flame, but neither the orange lithium line nor the sodium 
pair 5681, 5687 appear; yet there must be a maximum amount of alkalies in the slag, 
or in other words all the alkali metals in the charge are concentrated in the slag—• 
this maximum, however, being an extremely small quantity. 
It is worth while to take into account the heat of combustion of the elements in 
pig iron which are removed during the “blow,” and calculate, so far as data are avail¬ 
able, the absolute heating effect of their oxidation. Any calculations of the kind 
must necessarily be incomplete, owing to the specific heats of gases at high tempera¬ 
tures being undetermined, though these have been lately investigated by Berthelot 
and ViEiLLE,* also by Mallard and Le Chatelier.! The specific heats of molten 
iron and of ganister and slag are also wanting. 
The Combustible Elements in Pig Iron, with the Compounds formed, and their Heat 
of Combination (‘ Lecons sur les Metaux,’ A. Ditte). 
The names of the authorities are indicated as follows :—A., Andrews ; T. and H., 
Troost and Hautefeuille ; F. and S.,^ Favre and Silbermann ; T., Thomsen; 
B., Bertiiollet ; G., Grassi. 
Elements. 
Atomic 
mass. 
Kilo, heat-units 
developed from 
1 grm. atoTii. 
Compound 
formed. 
Kilo, heat units 
developed by 
1 grm. of each 
element. 
Authority. 
On 
63-4 
42-0 
CuoO solid 
0-662 
T. 
Mn 
55'0 
94-8 
MnO ,, 
1-72 
T. 
Si 
28-4 
219-2 
SiO.-, „ 
7-7 
T. and H., B. 
C 
120 
29-4 
CO gas 
2-45 
F. and S., 
G., A., T., B. 
s 
32 0 
69-2 
SO, „ 
2-2 
F. and S., T., B. 
p 
31-0 
363-8 
PoOr solid 
T. 
Fe 
56-0 
69-0 
FeO 
1-2 
T. 
In five tons of pig iron there are 5,080,240 grins. Let the composition of a pig iron 
be that which was quoted by Brunner, viz. :— 
Mn .... 3‘46 per cent.—- 175,776 gnus. 
C.3'18 ,, as grajihite 
Si. 1-96 ,, .= 99,573 „ 
C.0'75 ,, as combined carbon 
Total carbon = 3’93 ,, 199,653 
■* ‘Ann. de Chim. et de Pliys.,’ 6 ser., vol. 4, p. 66, 1885. 
t ‘ Journ. de Phys.,’ 2 ser,, vol. 4, p. 59, 1885. 
6 Y 2 
