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B.—CHEMISTRY. 77 
owing to war conditions, could not be maintained, and, owing to the demand 
for sulphuric acid for essential munitions of war, the supply for manufac- 
ture of superphosphate was strictly limited. Hence attention was directed 
to the examination of the results obtained by using finely ground natural 
mineral phosphates and basic slag. These insoluble phosphates were 
found to possess a considerably greater value as fertilisers than they had 
been given credit for. 
The shortage of food-stufis for cattle arose partly from decreasedimports, 
particularly of linseed, cotton seed, and grain, and partly from causes within 
the country, as for example the dilution of flour with maize and other cereals 
and the milling of the grain to obtain an increased percentage of flour for 
human food, whereby the quantity of milling offals was reduced. The 
attention of chemists was at once directed to the question of new or hitherto 
little-used food-stuffs. For some years prior to the war the importation 
into Continental countries, particularly Germany and France, of valuable 
oil-seeds had been rapidly increasing, thus providing oils for margarine 
manufacture and valuable cakes and meals as food for cattle. The case 
of palm-kernels, a valuable source of oil and cake, is a striking one, for 
British West Africa exported before the war about 250,000 tons, of which 
35,000 tons came to England and 181,000 tons to Germany, and a similar 
condition applied to copra, earth-nuts, and sesame seed. These and many 
other seeds began to be diverted to the British market, and the cakes or 
meals, after examination of feeding value, formed a useful addition to the 
food supplies, as was illustrated by the great increase in the manufacture 
of margarine. 
Home supplies were also explored, materials which had hitherto been 
discarded were tried, and waste material from a variety of sources was 
utilised. In all this the work of the chemist was essential. The ascer- 
taining of the composition of the material, of the digestibility coefficients 
of the various constituents, and of the feeding value of the material was 
the contribution of the chemist to this great problem of the nation. 
Since many of the war-time expedients mentioned above were of a 
makeshift character, it is not surprising that they did not survive when 
normal economic conditions arose. Thus, when sulphuric acid again 
became available, the troublesome use of nitre-cake was abandoned and 
blast-furnace flue-dust was no longer collected. It was disappointing 
that the nitrogen fixed in the large surplus stocks of explosives, both in 
the form of nitric esters and of nitrogen compounds, could not profitably 
be utilised. Many of the difficulties were overcome in the case of the nitric 
esters by the application of a process of alkaline hydrolysis, but the 
attempt was abandoned on account of the difficulties which arose during 
process in freeing the product from poisonous impurities and in putting 
it on an economic basis. 
The war-emergency work has had some lasting effects, of which may be 
mentioned the development of a process for making ‘ synthetic farmyard 
_ manure,’ the increased use of basic slag as a phosphatic fertiliser, and the 
increased attention that is being devoted to the newer nitrogenous fertilisers, 
more particularly those produced by fixation of atmospheric nitrogen. 
The lessons of the war have not, however, been entirely lost. The last 
report of the Development Commissioners, for the year ended 31st March, 
1923, shows advance in every direction. In addition to the sum available 
