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Rh it into 'dynamite' by the addition of an infusorial earth. Absorbed and retained by this or some other inert solid substance, the liquid explosive can be safely stored, transported, and used.

The essential constituents of all the most powerful military smokeless, propulsive ammunition are gun-cotton (nitro-cellulose) and nitro-glycerine. Hence cotton for making the one and oils and fats for the other are necessary to any country engaged in a modern war and unable to import the finished product.

On the subject of oils and fats I wrote to the press (The Times for September 18 and October 23) most unwillingly, and only when told by friends on one of the war committees of the Royal Society what was being permitted by the Government. I mentioned in the earlier letter that 'a friend interested in chemical works told me that it had come to the knowledge of his firm that there was a practical process for making glycerine from a certain material not previously used for the purpose. The firm informed the authorities, and within forty-eight hours the export of that material was prohibited.' There is no necessity for maintaining secrecy any longer, for the prohibition of the substance, linseed oil, was published in the papers on December 3,