REPORTS OF SOCIETIES. 
57 
a Sertularia, showing the zoophytes with extended tentacles; Mr. H. 
Miller, Pleurosigma formosum —a marine diatom—showing the striations; 
Mr. F. Derry, the “Fairy fly,” a species of Hymenoptera; Mr. W. H. 
Bowater, transverse section of oak, stained, mounted by himself ; 
Mr. R. M. Lloyd, the palate of Succinea putris; Mr. C. T. Parsons, the 
carmine Peziza, a beautiful fungus, on a twig; Mr. W. B. Grove, the 
fungus on mouldy bread; Mr. J. Morley, a fine specimen of Lepto- 
dora hyalina, mounted in pure spirit. Mr. R. W. Chase also exhibited 
three birds—the Little Auk, from the Faroe Islands ; the Reeve, from 
Ireland; and the Grasshopper Warbler, from Frankley. A large 
number of photographs of the earthquake at Ischia were also 
exhibited, by permission of Mr. Paxton Porter. 
BIRMINGHAM AND MIDLAND INSTITUTE SCIENTIFIC 
SOCIETY.—December 12th.—Mr. A. H. Hiorns read a paper on the 
“ Basic Bessemer Process.” Among the methods of refining iron in 
open vessels, the most important is that patented by Mr. Bessemer in 
1856, which has had so large a development in late years. It consists 
of blowing air through molten pig-iron so as to burn off the carbon, 
silicon, etc., leaving the iron in a malleable condition, or sufficient 
carbon to form steel. This was a great advance on the old method 
of refining in reverberatory furnaces, called puddling. In the latter, 
only about one hundred-weight is operated on at a time; in the 
former several tons, and in a much quicker time. The early 
apparatus was a closed vessel, with only one communication with 
the atmosphere by means of a curved opening. This was after¬ 
wards modified into a pear-shaped vessel with a large open mouth 
inclined to one side. At the present time concentric vessels are used 
with a wide mouth and straight neck, which prevents the metal from 
sticking to the neck as in the eccentric form. Originally two or three 
tons were operated upon at one time; now ten to fifteen tons is a 
usual quantity. The Bessemer converter has an acid lining formed of 
ganister, which prevents the elimination of phosphorus. In 1872 
Snelus showed that the retention of phosphorus was intimately related 
to the slag. When the slag is highly basic, as in puddling, the phos¬ 
phorus goes into the slag. He substituted dolomite bricks for the. 
ganister lining, and proved that steel could be made from pig-iron con¬ 
taining 2 per cent, phosphorus, and the phosphorus be reduced to OT per 
cent., but these results were not published. Messrs. Thomas and 
Gilchrist, after a series of experiments, prepared a paper to be read 
before the Iron and Steel Institute in 1878, and it is to their skill and 
perseverance, in conjunction with Mr. W. Richards, that the Basic 
process has achieved a technical and commercial success. They at first 
made bricks of Magnesian limestone like Snelus, but encountered great 
difficulties on account of the enormous shrinkage of the limestone. 
The lining is made of calcined and crushed dolomite, mixed with tar 
and rammed round a core which is afterwards removed. From 15 to 
25 per cent, of lime is charged in with the iron according to the 
amount of silicon in the pig. By this means the phosphorus is almost 
completely removed. It is a noteworthy fact that while in the 
Bessemer process the pig must be siliceous and contain very little 
phosphorus, with the Basic process the reverse is the case ; so that if 
the pig in the latter process does not contain 1£ to 2 per cent, of 
phosphorus, that element is added as ferro-phosphorus. Also in the 
Bessemer process gray iron is necessary; in the Basic process white 
iron is much preferred. The lining is not so durable in the latter as 
