4 
wT. eae 
FEBRUARY 22,) 1917 | - 
NATURE 
501 
the year 1913, a period undisturbed by domestic 
troubles or by the war, touched high-water mark in 
production and in consumption, with an output of 
287,430,000 tons, of which 189,000,000 tons were re- 
tained for home use. The number of employees was 
1,110,884, which gave an output per head of 259 tons. 
In 1914 the output fell to 2653 million tons; in 1915 
to 253 million tons. The demand for coal, however, 
increased with the enormous activity in the production 
of munitions, but the home consumption in 1914 was 
1843 million tons, and about the same figure for 1915. 
It was therefore the export trade which suffered. 
In ‘the period of forty-two years, from 1873 to 1914, 
we have raised 8,206,243,000 tons, and exported 
2,012,796,000 tons, or more than 244 per cent. The 
value of the coal raised was equal to more than 84 per 
cent. of the value of our whole mineral output. 
‘The questions arise naturally, What stocks have we? 
What inroads have we made on them? and How long 
will the stocks last? The last is too highly speculative 
and has too little real bearing on the question of 
economy to justify more than mention of the insuper- 
able difficulties of making such an estimate. 
Estimates of stock can, however, be made with some 
approximation. 
The following estimate was made by the Royal 
Commission (1905), the figures being in million tons. 
Estimated Coal Reserves, Royal Commission, 1905- 
Not exceeding 
4000 tt. 
Proved 
100,914 | 55239 
Unproved 40,721 — 
Totals 141,635 55239 
A few words may prove of interest about the Kent 
field, which was not included in the above estimate, 
and is of particular interest to us in London and of 
wider importarice because of its geographical situation 
in relation to the North Sea and the Channel. 
From borings which have gone to 2500 ft., Prof. 
H. S. Jevons considers it is established that over an 
area of 150 square miles the total thickness of the 
seamg (of 18 in. and above) is from 30 to 4o ft: If 
the area'is no greater than this—and there is reason 
to believe it is much more extensive—the reserves 
would be some 6000 million tons. 
The composition of one class is very close to the 
average composition of the high-class Welsh smoke- 
less. coals. -If the burning qualities of the coal are 
as good, and the seams are workable, the occurrence 
of such coal so conveniently situated in relation to 
several important naval bases may prove a valuable 
asset to the Royal Navy. 
Comparison may be made between our reserves and 
those of other countries. ; 
Of the European reserves, Germany possesses 54 per 
cent. of the whole; Great Britain 24 per cent.; Russia 
and Austria-Hungary about 7-6 per cent. each; and 
France 2-1 per cent. 
Of the world’s probable reserves, North America 
can Claim nearly 69 per cent., of which approximately 
40 per cent. lies in the United States. Asia comes 
next with 17-3 per cent., leaving Europe a poor third 
with about 10-5 per cent. 
Not only are we exhausting our supplies at a far 
higher proportionate rate than our nearest commer- 
cial rivals, but we are retaining for our home use a 
much smaller proportion of the output. 
It is clear that if Great Britain is to maintain her 
place among the great nations she must remain a 
great manufacturing centre, and this depends entirely 
on cheap fuel. The necessity for economy in place of 
waste is apparent, and enormous economies are un- 
doubtedly possible. : : ; 
NO. 2469, VOL. 98] 
One very important and very difficult question is 
that of export. It cannot be denied that in our 
export trade we have, to a large extent, developed our 
industrial greatness. But we must look at this ques- 
tion of export on a wider front than the immediate 
present or the immediate future. If, as our political 
economists tell us, our export is essential to our well- 
being, we must realise that it is at the cost of bring- 
ing the day rapidly nearer when industries will be 
hampered by dear coal—in other words, mortgaging 
the interests of posterity in the interest of the present 
and possibly a few succeeding generations. ; 
The suggestion which has been made for the re- 
imposition of a duty on export coal, the proceeds from 
which should be applied to the investigation of our 
coals and the development of schemes for the more 
economical utilisation of the coal we consume, would 
appear very sound. 
As Prof. H, S. Jevons so aptly puts it: ‘‘ English- 
men must take heed in the future to rely less upon 
exploiting our vast stores of national wealth, and more 
upon the resources which scientific skill and practical 
education can place at our disposal.” 
The economic use of coal is closely associated with 
the question- of the by-products—ammonium com- 
pounds and the tar—many important chemical indus- 
tries being dependent on the latter, whilst the small 
quantity of nitrogen in coal—averaging about 1-4 per 
cent.—furnishes our principal supplies of ammonia 
compounds. The sulphate of ammonia alone is a most 
important material as a fertiliser, and its importance 
to agriculture can scarcely be over-estimated. In the 
increased production of home-grown foodstuffs, gener- 
ally admitted to be a pressing question, it must un- 
doubtedly prove an important factor. It is one of the 
romances of science that by means of sulphate of 
ammonia we are actually returning to plant life nitro- 
gen derived from a previous vegetation which 
flourished millions of years ago. 
The tar is the most important of the by-products 
obtained, and certainly no substance has yielded so 
many valuable products for the service of man. All 
the vast number of beautiful dyes, of valuable drugs, 
disinfectants, flavouring essences and perfumes, and 
photographic developers are the outcome of the work 
of the chemist on the raw materials furnished by the 
tar. 
Benzene, the most important of the hydrocarbons 
obtained from the tar, has proved a valuable fuel for 
motor engines. In addition to that derived from the 
tar, further quantities may be obtained by washing 
the gas with heavy oils which dissolve the benzene 
and yield it up again on distillation. 
The importance of benzene as a fuel in lieu of petrol 
is very great; ample supplies of such a home product 
would do much to check artificial prices for petrol. It 
has been estimated that it would be possible to pro- 
duce annually some twelve million gallons from gas- 
works and sixty million gallons from coke ovens, if 
all coal were treated in recovery plant. 
Benzene is also employed for cleaning purposes 
(cloth, fabrics, etc.), and quantities are now converted 
to synthetic phenol (carbolic acid), from which picric 
acid (lyddite) is prepared. 
Another hydrocarbon closely allied to benzene is 
toluene, for which there is a great present demand 
for conversion into trinitrotoluene (T.N.T.), the power- 
ful high explosive. Quantities are now obtained by 
oil scrubbing of the gas and also synthetically from 
benzene. 
Phenol (carbolic acid) can be extracted directly from 
the light oil and carbolic oils by washing with caustic 
soda; also the closely allied cresylic acids. All yield 
high explosives on nitration. 
