May 14, 1885] 
not the least reason to anticipate. But, as I wrote many years 
ago, however mournful and unwelcome this proposition may be, 
we have the satisfaction of knowing that we are now laying the 
foundations of prosperous and mighty kingdoms in various parts 
of the world, which we hope will be the strongholds of virtue, 
of order, and of freedom. When our great manufactories shall 
have crumbled into ruins, and their sites have become green 
pastures or golden corn-fields, the old country may yet be 
precious in the eyes of her children. Every spot of her soil will 
be classic, and command reverential respect. There is no other 
land more worthy of everlasting remembrance, whether as to its 
heroes, its poets, its philosophers, its statesmen, or its philan- 
thropists. The glory of Old England may, after all, not depart. 
On the sites of her soot-stained Birminghams and Manchesters, 
new and splendid cities may arise, where the merchant-princes 
of Anglo-Saxon descent, from the remotest regions of the globe, 
shall rejoice to dwell and end their days in peace.” 
After the address the President presented the Bessemer Medal 
to -Mr. Lowthian Bell for delivery to Prof. Akermann, after 
which the papers were read. The first paper read was that of 
Mr. Lowthian Bell, on ‘‘The Blast-Furnace Value of Coke, 
from which the Products of Distillation from the Coal used in 
its Manufacture have been collected.” |The experiments which 
formed the foundation of the paper were made upon the same 
coal coked in the beehive and Simon Carve’s oven, the total 
quantity of coke operated upon being 5605 tons; it was found 
that the beehive coke was about 10 per cent. more economical, 
although the other was 13°83 per cent. denser. In order to 
ascertain the cause of the inferiority, samples were finely ground 
and analysed. Similar samples were exposed for half an hour 
to the full heat—sufficient to soften porcelain—of a gas blast- 
furnace, access of air being excluded by placing the crucible 
containing the sample within a larger one and covering it with 
charcoal. From the loss of weight and the analysis of the original 
and residual coke, and from the previously-ascertained moisture, 
it was found that 5°23 per cent. of the Simon Carve’s coke was 
expelled by ignition, and 3°27 per cent. of the beehive. This 
accounts for an inferiority of 1°96 per cent. only out of about 10 
percent. It is, however, a well-known fact that certain forms 
of carbon are less easily burnt than others, and the author 
sought to account for the superiority of beehive coke in this 
manner, and found it to be due to the less solvent action of 
carbonic acid upon it. 
t the Wednesday evening meeting Dr. H. C. Sorby, F.R.S., 
gave an account of his microscopical examination of the struc- 
ture of iron and steel. His results were based upon the 
examination of flat surfaces, carefully ground and polished, as 
the study of fractured surfaces is unsatisfactory, not only on 
account of optical difficulties, but because a fracture shows the 
line of weakness between the crystals and not their internal 
structure. Jn some cases the surfaces were acted upon by very 
dilute nitric acid to develop the structure; in others it was 
found best to polish with dry rouge on parchment, and not to 
use acid. Thin glass covers were afterwards mounted over the 
surface with Canada balsam. The objects thus prepared were 
examined by means of two special kinds of surface illumination, 
viz. first the side parabolic reflector now common, but which the 
author believes was originally made for this purpose, which gives 
oblique light ; and secondly, by means of a small silver reflector 
covering half the object-glass, which throws the light directly 
down on the object, from which it is reflected back through the 
other half of the lens. With oblique illumination a polished 
surface looks black, but, with direct, bright and metallic. A 
truly black substance looks black in both cases. A magnifying 
power of about sixty linear is most generally suitable, but the 
sections will beara higher perfectly well. The lecturer exhibited 
photographs and drawings of the microscopic appearance of the 
surfaces, the peculiarities of which he described. 
The following is a summary of some of the chief results :— 
Tron containing little or no carbon, and of uniform character, 
shows little, if any change, when acted upon by dilute acid, and 
no well-marked structure is developed. Hammered blooms 
show an intimate mixture of varying crystals of iron, with minute 
or larger portions of slag. In iron bars rolled /o/, the slag is 
drawn out into long thin rods, which in some cases are so 
humerous as to forma very considerable portion of the whole 
bulk, whilst the iron shows no elongation of the ultimate crystals, 
the metal apparently recrystallising on cooling. When hammered 
cold, the crystals are compressed, broken up, and elongated in 
the line of the bar. Many specimens of malleable iron show 
clearly that two constituents are present, viz. iron, and a com- 
NATURE 
| 
39 
pound of iron and carbon, which has a pearly structure ; one of 
these is like the main constituent of such bar iron as contains 
little or no carbon, having no trace of linear marking, after 
being acted upon by diluteacid, whereas the other constituent shows 
linear markings, varying in distance, but often about 1-20,o00th 
of an inch apart, which, when the acid has acted toa proper 
extent, gives rise to all the splendid colours of mother-of-pearl, 
the tints being raised when the section is seen in water, and 
still more so when mounted in balsam. By oblique and direct 
illumination the colours are nearly complementary. Swedish 
iron partly converted into blister steel by cementation, shows 2 
mixture of well-formed crystals of free iron and of the pearly 
compound in the centre; around this a ring of the pearly com- 
pound, with colours of great variety and beauty ; whilst on the out- 
side is a part in which occurs a network of veins of an extremely 
hard substance, giving an intensely brilliant reflection and no 
trace of colour, which seems to contain more carbon than the 
pearly constituent. The three constituents just described are 
totally distinct from one another. There is no more passage 
from one to the other than there is between the mica, felspar, 
and quartz of granite. 
The varying character of ingots of soft and hard steel to 
a great extent depends on the varying proportion of the 
three principal constituents. Soft Bessemer steel is seen to 
be a mixture of free iron andthe pearly compound. In medium 
steel this latter occurs almost alone, whereas in hard steel there 
is little, if any, free iron, but numerous thin plates of the very 
hard compound. Besides these three constituents in steel, the 
microscope gives evidence in cast-iron of the presence of graphite 
and silicon. The specimen of spiegeleisen studied, consisted 
mainly of the intensely hard compound, crystallised in large 
plates, the inter-spaces being filled up with a mixture of very 
much smaller crystals with a little of the pearly substance, so as 
to have a most beautiful and fine-grained structure. Taken, 
then, as awhole, the various kinds of iron and steel are seen to 
be varying mixtures of three or four out of six or seven substances 
having very different properties, viz. free iron, the pearly com- 
pound with carbon, the intensely hard compounds, probably 
with more carbon; the residual, probably variable, substance ; 
graphite ; possibly crystallised silicon ; slag, including fused iron 
oxide. 
On the second day the attention of the meeting was occupied 
with the subject of the coking of coal by different processes and 
the recovery of bye-products. Mr. Head’s paper contained a 
description of a modified form of the Siemens old type gas- 
producer, in which the latter result is effected by dividing the 
gas-producer by means of a vertical wall into two compartments, 
one of which receives the hydrocarbons—the volatile constituents 
of the coal—and the other the carbonic oxide formed by the 
decomposition of its solid carbonaceous matter. Two other 
papers referred to results obtained in connection with the Simon- 
Carve’s coking process. Prof. Armstrong’s note with reference 
to the method’s proposed for coking coal and recovering volatile 
matter has much scientific interest, and we propose to refer to it 
shortly. The problem consists in as complete a recovery as 
possible of the matters latent in coal, in the most economical 
manner and advantageous forms, the treatment depending upon 
the class of coal acted upon. The author considers the com- 
pounds in coal to be mainly of two kinds—phenolic compounds, 
which are the primary source of the phenols (carbolic acid, &c.) 
contained in coal tar; and paraffinoid compounds, capable of 
yielding hydrocarbons such as are obtained on distilling shale ; 
the high-temperature tars such as are obtained at gas-works, not 
being primary but secondary products of distillation, may be 
considered final products, the quality of which it will be im- 
possible to improve, whereas the object should be to produce 
low-temperature tars, which by after-treatment might be made 
to produce a large proportion of benzene and other valuable 
products. ‘ 
The author’s idea of a theoretically perfect coking oven is one 
more or less like the present beehive, with the upper part 
extended. Heat should be ‘vadiated upon the surface of the 
charge of coal, which would soon become coked, thus forming a 
protecting layer, below which distillation would take place, the 
products of distillation being sucked away as rapidly as possible 
through the cool bottom of the oven. The products of combus- 
tion which penetrate below would carry no oxygen with them. 
On this account, and on account of the large volume of steam 
and other gases generated within the mass, and of the low tem- 
perature, the ammonia would probably almost entirely escape 
destruction. The gas would be of low illuminating quality, but 
