ee 
J. M. Silliman—Examination of the Bessemer Flame. 299 
the flame is of an ashy blue color with streaks and flashes of 
crimson ; the edges being sometimes of a purplish hue. At this 
point surrounding objects are illuminated, and the converter 
becomes distinctly visible. A wreath of crimson is seen sur- 
rounding the flame where it strikes the chimney. By the middle 
of this period the crimson almost entirely disappears from the 
body of the flame, leaving only a slight cone at its base, and a 
border of greenish hue makes its appearance, and gradually 
grows more decided. Streaks of a dark blue color are also seen 
in the body of the flame. 
"he beginning of the third period is scarcely indicated to the 
naked eye, though the flame becomes somewhat weakened, 
and after a few minutes shows dark streaks running through it. 
Through the glasses at the commencement of this period the rose- 
colored cone begins to expand and deepen, the greenish sheath 
is more decided, while streaks of dark and green are visible. 
After a few minutes the change becomes very rapid, a few 
seconds only being required to reduce the flame from rose-color 
to the deep crimson non-illuminating gas, as at first, and again 
the converter is lost to view, by which time the blast should 
have been turned o: 
The gradual fading of the crimson from the beginning of the 
blow and its deepening at the termination of the process, as well 
as the erimson band at the base of the flame and the wreath of 
crimson surrounding the flame at the chimney, tend to confirm 
Mr. Rowan’s views, which are, that the different shades of crim- 
period than at any other. a; 
ri the base of the flame and the wreath of 
rose-colored cone extending from the base at the center, which 
we would naturally consider the hottest part of the flame; but, as 
im the flame of the Bunsen burner, the hottest part is in its outer 
sheath, the conditions of combustion in both being similar, it 
1s probable that that part of the flame occupied by the cone is 
ata lower temperature than that surrounding it. 
