AucusT 24, 1899] 
NATURE 
493 
addition to the charges in the blast furnace, by agglomeration 
previously to charging in the blast furnace, as a refining or 
softening material in the open-hearth furnace, and for the pro- 
duction of sponge iron for use in the open-hearth furnace. 
Mr. H. C. McNeill next read a lengthy paper on some forms 
of magnetic separators and their application to different ores. 
The machines described were those invented by Wenstrom, by 
Delvik-Gréndal, by Heberle, and by Wetherilland the Monarch 
separator. Results obtained in practice in Sweden were dis- 
cussed, and numerous illustrations were given. In the discus- 
sion of these two papers valuable remarks were made by Mr. 
James Riley, Mr. G. J. Snelus, F.R.S., Sir Lowthian Bell, 
Mr. Stead and others. 
A new casting machine for blast furnaces was then described 
by Mr. R. H. Wainford. It is an ingenious apparatus for casting 
sandless pig iron in insulated moulds, so as to maintain a good 
crystalline fracture, equal to that of the pig iron made in sand 
beds, at a reduced cost of production. The advantages and 
disadvantages of this apparatus were discussed by Mr. FE. 
Windsor-Richards, Mr. W. Hawdon, Mr. Cooper and Sir 
Lowthian Bell. 
Mr. Syed Ali Bilgrami, Secretary to H.H. the Nizam’s 
Government Public Works Department, Railways and Mines, 
then read a paper on the iron industry in Hyderabad. He 
described the geological structure of the Nizam’s-territory, and 
the various iron ore deposits met with. 
Some interesting facts were brought forward by Major R. H. 
Mahon, of Cossipore, relating to the possibility of manufacturing 
at a profit iron and steel in India. In the absence of the author 
this paper was read by the Secretary, Mr. Bennett H. Brough. 
An interesting discussion followed, in which Mr. Bauerman and 
Mr. R. Price-Williams took part. The meeting was then ad- 
journed until Wednesday, when a paper by Mr. C. H. Ridsdale 
was read. The microscopic examination of steel is a subject on 
which a good deal has been written during the last few years. 
Most of the papers hitherto published have dealt with the matter 
from a purely scientific point of view. The aim of the exhaustive 
paper contributed by Mr. C. H. Ridsdale was to show the 
practical value of the microscope to the steel maker and user at 
the present day. The time has now arrived, he points out, 
when it should be recognised that composition only indicates 
such well-defined effects as are generally understood without 
certain narrow limits of treatment, which are termed ‘‘ normal.” 
Outside these limits the effect of the treatment far outweighs 
that of the composition. In the discussion of this paper the 
President, Mr. Greiner, Mr. Harbord and Mr. Stead took 
art. 
Mr. J. W. Miller contributed a paper on pig iron fractures 
and their value in foundry practice. He gave instances of the 
loss sustained by the manufacture of pig iron owing to the 
present method of grading pig iron by fracture. 
The present position of the solution theory of carburised iron 
was discussed by Dr. A. Stansfield. The conclusions he has 
arrived at with respect to the atomic complexity in carbon are 
as follows :— 
The carbon in molten iron is ina state of simple solution ; 
the molecule of carbon must then contain one or two atoms, 
and is probably monatomic. The solidified iron is in the y 
state and contains free carbon in solution. The molecular 
weight of this carbon has not been discussed, but it is probably 
the same as that in the molten iron. The carbon in solid 
solution combines with iron, on cooling, to form a carbide, 
which is probably expressed by the formula 2(Fe;C). When, 
on further cooling, this carbide falls out of solution as cementite, 
its formula may become more complicated ; the solution theory 
affords no information on this point ; but Sir W. Roberts-Austen 
stated in his presidential address that the nature of the products 
of its solution in acids led to the conclusion that the molecule 
may contain six atoms of carbon, and is at least as complex as 
would be indicated by the formula 6(Fe,C). There appears to 
be a belief that the solution theory is in a sense opposed to, 
and has gone far to supplant, the older allotropic theory ; but 
this paper will, it is hoped, effectually dissipate such an error, 
as it shows how entirely the solution theory of the relations of 
carbon and iron involves the allotropic changes with which the 
distinguished name of Osmond is so inseparably connected. 
In the discussion of this paper Mr. Snelus, Mr. Hadfield and 
Mr. Stead took part. 
Mr. A. Sauveur, of Boston, contributed a paper on the changes 
of structure brought about in steel by thermal and mechanical 
NO. 1556, VOL. 60] 
treatment. Ife showed that as the smaller the grains of the 
metal the more ductile and tough it will be, as the finest 
possible structure results from heating to Brinell’s point W, the 
temperature at which the passage of cement carbon into harden- 
ing carbon during the heating of steel takes place, namely, 655° 
to 730° C., it is evident that every finished piece of unhardened 
steel should as a last treatment be heated to that temperature. 
Prof. E. D. Campbell, of Ann Arbor, Michigan, con- 
tributed a paper on the constitution of steel. The general 
method employed for studying the products of steel was to 
dissolve the steel in hydrochloric acid, pass the gas evolved 
through bromine in order to convert unsaturated hydrocarbons 
of the general formula C,H,,, into their di-brom derivatives 
C,,H,,,Br, ; the gas passing through the bromine being measured, 
and the carbon existing as gaseous paraffins being determined by 
explosion and absorption of the carbon dioxide produced. The 
di-brom derivatives, after proper purification, drying, and 
weighing, were analysed and fractionally distilled for the 
purpose of qualitatively identifying the various constituents ; 
although the fractional distillation of the di-brom derivatives 
had shown the presence of ethylene, propylene, butylene, 
pentylene, and hexylene di-bromides, and dibutylene tetra- 
bromide, later investigations had shown that this last product 
was the result of the polymerisation under the influence of heat 
during distillation of butylene di-bromide, and was not present 
to any considerable extent, at least in the original derivatives. 
Although the di-brom derivatives from ethylene dibromide 
(C,H,Br,) to hexylene dibromide (C,H,.Br,) had been detected 
qualitatively, the separation of the various derivatives by frac- 
tional distillation zz vacuo was not sufficiently sharp to give 
accurate quantitative results in regard to the amount of each 
constituent present. From the percentage of bromine in the 
di-brom derivatives the average number of carbon atoms in the 
molecule was calculated, the results of the examination of a 
few samples of steel by the above method being shown in the 
following table :-— 
| 3 bg | 83 Bs 
63 /s,4|/58.|58 | Seu ease 
| Mee ;a2 ‘946 S35 ood (Saad 
N | Heat aS Bes | | tote ;o5 | oa3 Bans 
ame. | treatment. 8 8 82$ 4 g & ga} o Bs 23 os 
$8 | 588) Seca) 53 | FERS sees 
Ad |A DU] Sg 58 Aso /eokU 
2 a [Vp] 5 os 
F |Annealed | 0°55] 37°1 | 33°6| 29°3 | 72°56) 4°32 
Hardened 
FE and 0°55| 25°0 75°65 | 3°67 
tempered \ 
C Annealed 1°14) 43°4 | 37°9 | 18:7 | 73°85 | 4°05 
C |Hardened| 1°14) 29°0 | 48°6 | 22°4 | 77°61 | 3°31 
D_sAnnealed 1:28] 31:0 | 44°3 | 24°7 | 77°80| 3°26 
‘Pure Car- 
|bide from] > 6°64) 35°3 | 25°2 | 39°5 4°41 
Danneal’d 
The number of carbon atoms in the carbon molecule of the 
derivatives from the pure carbide, given in the above table, was 
obtained from the analysis of the gas by dividing the volume of 
carbon dioxide, produced from the explosion of the olefines, by 
the volume of the olefines exploded. The hypothesis suggested 
by the author made the fundamental assumption that carbon 
formed with iron a series of compounds which might properly 
be termed “ferrocarbons,” on account of their similarity in 
structure to hydrocarbons. This series of ferrocarbons had 
the empirical formula (CFe,),, 3 or, C,Fes,, and should be con- 
sidered as being derived from the hydrocarbons of the olefine 
series with the general formula C,,H,, by the replacement of the 
H, by the bivalent group Fes. These ferrocarbons, dissolved 
in hydrochloric acid, yield as their primary products of solution 
the corresponding olefines and hydrogen. 
During the meeting excursions were arranged to the loco- 
motive works at Horwich, to the Simon-Carvés coke ovens 
near Barnsley, to the Manchester Ship Canal, to the ironworks 
of Platt Brothers, Ltd., at Oldham, to the boiler works of 
Galloways, Ltd., and to the steel works at Crewe; and 
hospitality was lavishly dispensed to the members by the Duke 
of Devonshire at Chatsworth, by the Lord Mayor of Manchester, 
and by the Mayor of Salford. 
