OF FLAMES RESULTING FRO^I BESSE^JER PROCESSES. 
48;l 
Manganese . 
Silicon . 
Phosphorus 
Sulphur . 
Carbon . 
about 1 ‘0 per cent. 
0-08 
,, 3'4 
The blow may be divided into three stages. The first stage ends when the flame 
drops, indicating that the carbon has burnt out. The second stage ends when the 
vessel is turned down for a sample of the metal to he taken and the slag poured off*. 
More lime is then added, and the blow is continued for a few seconds to complete the 
removal of the phosphorus ; this forms the third stage. 
First Stage .—The average duration of this was 12 minutes and 20 seconds. The 
blow begins with the expulsion of a large cpiantity of lime dust, and as soon as this 
has cleared away a flame is visible. It has a yellow or yellowish-red colour, the 
colour being probably caused by hydrocarbons from the tarry matter in the lining of 
the vessel. The flame grows larger and brighter, and assumes the usual appearance 
observed in the “ acid ” process. Sparks are thrown off*, which in turn throw oft* 
other sparks; these are succeeded by larger showers of sparks and a louder roaring of 
the flame. When, after a time, the flame gets thin, some fume is seen; then the 
flame drops and the sparks do not throw off* scintillations. 
Second Stage. —This, technically known as the “ over-blow,” lasts about 5^ minutes. 
In the earlier part the flame is very short; it gradually extends, and the fume arises 
very copiously. It was noticed that the cloud of fume was yellower than that seen 
at Crewe and Dowlais in the “ acid” process. On one occasion tlie fume was observed 
to have a rich purple colour when viewed by transmitted light, which colour faded 
gradually and became more like brown umber; the flame gradually increased in 
density until it became very brilliant indeed, but its colour was always of a golden- 
yellow, until sometimes it resembled phosphorus burning in oxygen. Slag is thrown 
out in large quantities, and with a shower of sparks, just prior to the converter being- 
turned down. 
.Owing to the exigencies in the arrangement of the Bessemer plant and the nature 
of the operations carried on, it was found that the only point of observation available 
was a gallery at one end of a row of four converters, and when the most distant 
of these vessels was in use nearly all the details of the “ blow” as photographed else¬ 
where in the “ acid” process were absent. 
For instance, the manganese bands were not defined or even clearly visible. Then 
again, the spectra were complicated by a superposed feeble solar spectrum. Only 
those vessels nearest the instrument yielded satisfactory photographs. It was proved 
eventually that the lime dust and other dust and smoke in the air reflected the sun’s 
rays and caused an overlying solar spectrum to appear. To get rid of this it became 
necessary to make all the observations during the evening after dark. 
Having described the course of the “blow” in the Thomas-Gilchrist process, it will 
3 Q 2 
