NovVEMBER 13, 1913] 
large town. In the same way the methods of burning 
gas had been very inefficient until recently the chemist 
had come in. He asked for legislation to secure the 
proper use of coal, and urged the appointment of a 
royal committee of experts to organise and direct 
experimental work. The efforts of the remaining 
speakers were directed to show how economy had been 
secured in various branches of the subject as the result 
of the application of scientific inquiry. 
Dr. Beilby dealt with low temperature carbonisation, 
describing for the first time a form of apparatus which 
he had devised in which coal could be exposed to the 
action of heat in thin layers. This consisted of a 
column heated externally in a gas-fired oven at 400° 
to 450°, and fitted internally with a series of sloping 
shelves. The coal was fed mechanically to the top 
of the column and the shelves jolted, so the coal 
passed over the whole series from top to bottom in 
a sheet of from 2 in. to 24 in. in thickness. The time 
required was about an hour and a half, and a unit 
with a capacity of fifteen tons per day had been 
reached. He was satisfied that the production of a 
mechanically perfect apparatus into which small coal 
was automatically fed, passed through a distilling 
zone, and finally passed through a cooling chamber, 
only required a little more patient step by step 
development. Present disadvantages of the apparatus 
were that it would only work smoothly with non- 
caking coal and that it tended to break down the coal 
into small stuff. The coke from this plant had proved 
quite satisfactory in water-gas plant, and when aggre- 
gated into briquettes with about 7 percent. of pitch it 
had proved eminently suited for domestic fuel. 
Dr. H. G. Colman followed with a comprehensive 
account as to how far the gas industry was helping 
towards the economic use of fuel. The industry takes 
at present sixteen million tons of coal per annum. 
A steadily increasing proportion of the gas output is 
now employed for heating. The intrinsic luminosity 
of the gas was now only of minor significance, the 
calorific power being vastly more important. The cost 
at which gas was sold was steadily decreasing owing 
to greatly improved technological methods in the 
manufacture, to economies due to the larger scale on 
which operations were carried out, and to the in- 
creased value of some of the by-products. 
Twenty-five per cent. of the heat units in the coal 
were obtained in the gas, 50 per cent. in the coke, 
and about 5 per cent. in the tar, the remainder being 
used in the process of manufacture. At present only 
about 20 per cent. of the nitrogen present in the coal 
is recovered in the form of ammonia. The efficiency 
of gas when used for lighting and for domestic 
heating and cooking was discussed, and its present 
increasing employment on a large scale for other 
industrial purposes was mentioned. In Birmingham 
this use accounts for some 8 per cent. of the total 
output. 
Recent progress in gas-fire science was the subject 
summarised by Mr. H. James Yates. The drawbacks 
of the early gas fire were explained, and the evolution 
of the modern form of radiating fire, in which the 
fire-front consists of a series of hollow fire-clay 
columns (radiants), each flame rising into the cavity 
of its radiant, care being taken to prevent any in- 
fringement on the inner cone of the flame. Radia- 
tion has taken the place of convection as the mode of 
heat transference, and more than 50 per cent. of the 
net heat combustion of the gas is delivered as radiant 
energy. The author next enlarged on the testing of 
gas fires. The important question of ventilating effect 
was next considered. To ensure good ventilation with- 
out any sacrifice of radiant efficiency, an adequate 
vertical distance between the top of the radiants and 
the bottom of the canopy must be preserved. The 
NO. 2298, VOL. 92] 
NATURE 
oos 
entire change in the construction principle of gas fires 
was leading to their general adoption. To-day there 
were upwards of 350,000 gas fires in use in London 
alone. 
Prof. W. A. Bone, who spoke at some length, dealt 
with the use of cheap gaseous fuel generated at or 
near the point at which it was to be used. He dis- 
cussed the cost of generating water-gas and of 
ammonia-recovery producer gas, the latter being 
equivalent to coal-gas at 4d. per 1000 cubic feet. He 
outlined recent improvements in connection with a 
modern steel works plant which had led to the sub- 
stitution of producer gas by a mixture of blast-furnace 
gas and coke-oven gas. This resulted in the aboli- 
tion of the gas-producer with an economy of 2 to 
3 cwt, of coal per ton of steel produced. Progress 
of this type represented an enormous economy in 
the use of coal; in addition, both tar and ammonia 
were recovered from the coal used. 
Dr. R. V. Wheeler, speaking on the composition of 
coal, described a method of discriminating between 
coking and non-coking coals, his object being to ex- 
plain the variations in the bituminous coals which 
cannot be accounted for by the differences which occur 
in their ultimate chemical composition. Coal was 
extracted with pyridine, and this extract separated 
further by partial solution in chloroform. 
Dr. R. Lessing returned to the economics of 
domestic coal consumption, pointing out that any great 
increase in the use of coal-gas in the future would 
result in an over-production of gas-coke. He advo- 
cated more attention being paid to low-temperature 
carbonisation. 
Mr. W. H. Patterson spoke with regard to the 
improvement of combustion and the blending of coals. 
The discussion then became general. 
A lengthy paper by Messrs. J. F. Liverseege and 
A. W. Knapp entitled ‘The Action of an Alkaline 
Natural Water on Lead” concluded the sitting. The 
subject is now one of wide importance since so many of 
the large cities are now using very soft water gathered 
in distant hilly country. Such water may corrode or 
erode lead pipes, and requires treatment to prevent 
any danger arising from this action. The behaviour 
of the Birmingham water, gathered chiefly in Wales, 
towards lead pipes and sheet lead has been very 
thoroughly investigated by the authors, who find that 
given sufficient oxygen, the alkalinity of the water is 
the principal factor determining the amount of erosion. 
The use of lime as a preventative was not found satis- 
factory, but protection was given by the addition of 
four parts of calcium carbonate -or two parts of 
calcium bicarbonate per 100,000. In practice a small 
proportion of powdered chalk is added to the water in 
Wales. The authors gave a full account of their 
methods of analysis. These were criticised by Prof. 
P. F. Frankland, who contended that the employment 
of Houston’s test for determining the action of the 
water on lead was valueless, and that the only suit- 
able test is to place the water in a corked lead pipe. 
The authors determined the alkalinity of the water 
by titration. This did not represent the true condi- 
tion of the water, as it overlooked the dissolved 
carbon dioxide. He advised the use of Walker’s 
method. 
Radio-active Elements. 
The discussion on radio-active elements and the 
periodic law attracted a very large audience. Unfor- 
tunately the counter-attractions of Sir J. J. Thomson’s 
new gas limited it to an hour and a half, but Mr. 
Soddy, who opened it, was properly very brief. His 
main conclusion, based on the existence of chemically 
identical and non-separable groups of elements may be 
summarised as follows :— 
