January 4, 1917] 
and fresh-water deposits of Pliocene age are much 
more widely distributed in south-east England than is 
commonly supposed to be the case. The late Mr. 
Charles Dawson’s discovery of rolled remains of 
Pliocene mammals at Piltdown makes it especially 
desirable to re-examine all the superficial deposits in 
the Wealden area. Mr. A. S. Kennard contributes an 
important summary of the results of his long-con- 
tinued researches in English Pleistocene geology. He 
concludes that there is no evidence of more than one 
glacial period, which occurred towards the close of the 
Pleistocene, and is represented near London by the 
Ponders End arctic bed. He is also of opinion that 
before the end of Pliocene times man was already in 
the Palzolithic stage of culture in this country. 
Tue recently published Bulletin of the Imperial In- 
stitute (vol. xiv., No. 3) contains a brief but highly 
interesting description of the new Udi-Okwogu coal- 
field of Southern Nigeria, which is now being ener- 
getically developed. It lies immediately to the east of 
the River Niger, and has been opened by means of 
a railway line running northwards from Port Harcourt, 
which has already reached the coalfield and is being 
continued. The coal is of Cretaceous age, and a num- 
ber of seams, up to six in the Udi district, have been 
proved; four of these are considered workable, with 
thicknesses ranging from 2 ft. to 5 ft. 8 in. The coaf 
is semi-bituminous, and contains a high proportion 
of volatile matter, averaging about 4o per cent. on the 
ash-free coal. The percentage of ash varies within 
very wide limits; in many of the samples it is between 
4 and 8 per cent., but is very much higher in some 
of the others; the coal is everywhere of a non-coking 
character. The calorific power is, of course, variable, 
but not very high as a rule, most of the samples giving 
6000 to 7ooo calories. A certain amount of dévelop- 
ment work has already been done, the quantity pro- 
duced up to the end of 1915 having been 7812 tons. 
It is unnecessary to point out that this discovery is of 
the highest economic importance, and will necessarily 
prove to be a factor of the utmost value in the indus- 
trial development of our West African Colonies. 
An informing lecture on the subject of ‘‘ The British 
Coal-Tar Colour Industry and its Difficulties in Time 
of War” was delivered at the Society of Arts on 
December 8 by Mr. C. M. Whittaker, head of the 
experimental dye-house of British Dyes, Limited. The 
lecturer replied to the criticism directed at British dye- 
producers for not assisting dye-users with pattern cards 
and expert advice in dye practice by referring to the 
manual of dyeing issued in five languages so far back 
as 1906 by Messrs. Read Holliday and Sons, Ltd. 
He also pointed out the difficulty of producing dyes of 
well-known constitution owing to the circumstance 
that the primary coal-tar products essential in this 
manufacture are required for the production of high 
explosives. In war-time the first duty of the coal-tar 
industry is to furnish the munitions of war, after 
which the next important task is the production of 
colours needed for the military and naval equipments 
of the British, Colonial, and Allied Governments. 
That these requirements have been satisfied is a great 
achievement, which should be remembered by the pri- 
vate dye-users, whose demands necessarily take a third 
place. The lecture deals with other shortages of raw 
materials, and shows how very promising has been the 
progress of the British dye industry in spite of these 
numerous handicaps. Notwithstanding all these adverse 
circumstances, the shares of leading colour-consuming 
companies in this country have appreciated considerably 
during the war, and the dyeing trade has never been so 
prosperous. Continued progress depends on the highly 
trained chemist, and research is now being organised 
NO. 2462, VOL. 98] 
NATURE 
357 
on a scale never before attempted in Great Britain. 
One of the first-fruits of this endeavour is the produc- 
tion of chloranthrene-blue, made by British Dyes, 
Limited. In the discussion, the chairman, Sir William 
Tilden, referred to the encouraging outlook to be de- 
rived from the lecture. In replying to various ques- 
tions the lecturer stated that bromine was the only 
product for which we should have to depend on Ger- 
many. The dye-makers had now mended their ways 
in regard to teaching institutions, and the grant of 
50ool. for dye research by British Dyes, Limited, to 
the Huddersfield Technical College was a practical 
proof of this. As regards khaki dyes, the British pro- 
ductions were equal in fastness to any dyes made 
abroad. 
In 1913 the Rubber Research Committee in Ceylon, 
in co-operation with the Department of Agriculture in 
the Colony, started a scheme of research work, to be 
carried out partly on plantations in the island and 
partly at the Imperial Institute in London. The work 
in Ceylon includes the preparation of rubber in various 
ways and under different conditions, with the view of 
ascertaining the effect of the several factors on the 
quality of the rubber. The samples so prepared are 
sent to the Imperial Institute, where they are chemic- 
ally examined, vulcanised, and their mechanical pro- 
perties determined. Some results of this’ work are 
described in Bulletins 23 and 24, issued recently by 
the Department of Agriculture in Ceylon, which con- 
tains a number of interim reports from the Imperial 
Institute. It appears from these reports that as re- 
gards tensile stress required to rupture and elongation 
at the point of rupture, well-prepared Ceylon planta- 
tion rubber is in no way inferior to ‘‘fine hard Para” 
rubber from Brazil. The variability in properties of 
plantation rubber of which manufacturers have com- 
plained appears to be limited to the ‘time of vul- 
canisation,” which, according to these reports, may 
vary within wide enough limits to cause trouble in the 
smooth working of a factory. The cause of this varia- 
tion is being systematically sought by a careful study 
of the effects of various coagulants, “improvers,” 
mechanical treatment, etc., employed in the process of 
preparation, on the working quality of the rubber, and 
especially on its ‘‘time of vulcanisation.”” Attention is 
also being given in Ceylon to the experimental tapping 
of Hevea trees. In Bulletin No. 25 Mr. Petch gives 
a further instalment of the results of this work, which 
has been in progress since 1912, and is designed to 
ascertain the difference in yield and the final effect on 
the trees of methods of tapping, which differ in the 
time interval allowed for resting the trees and in the 
spacing adopted between the tapping cuts. The results 
already obtained are of considerable interest, but do 
not permit of final conclusions being drawn. 
Tue practical value of the storm warnings issued by 
the Meteorological Department at Calcutta has twice 
been illustrated within the past two months, says the 
Pioneer Mail of December 2 last. Madras had due 
notice of the approach of the gale which visited it on 
November 29, the ‘‘ Great Danger” signal having been 
hoisted a considerable time before the arrival of the 
storm. Similarlv the hoisting of the “Great Danger” 
signal warned Calcutta of the approach of the storm 
of September 21, and the Committee of the Bengal 
Chamber of Commerce has publicly expressed its 
appreciation of the ‘‘usefulness and efficiency” of the 
work of the Meteorological Department on that occa- 
sion. ‘‘The warnings,” it states, ‘were communi- 
cated to the public in good time before the storm 
actually broke, and proper precautions were conse- 
quently taken. The result was that the casualties to 
shipping were confined to a few launches and boats, 
no large vessels being sunk or damaged.”’ 
