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Rh product was obtained of remarkable purity, considering its origin, and suitable for the manufacture of cordite R.D.B.

The result is an example of the successful application of chemical technical control to secure a product of standard uniform quality, and by reason of the quality of low viscosity of the nitrated product a very considerable economy in the ether-alcohol, for gelatinizing the nitro-cellulose. The methods for determining the viscosity of the cellulose, and a method for determining ligneous impurities in the cellulose (Trans. Chem. Soc. 1920, 117, 473 and 479, and Jour. Soc. Chem. Industry, 1920, 39, 81 T) were worked out at the Research Department, Wool- wich. The application of this work on cellulose by the Depart- ment of Explosives Supply is described in Jour. Soc. Chem. Industry, vol. 39, 333 T.

The United States supplied large quantities of nitro-ccllulose propellant for the Allies and for its own army, and used as raw material a considerable proportion of the shorter fibre " waste " from the delinted cotton seed. During the last three months of the war the total production of cellulose nitrate material in the United States was at the rate of 5,000 tons a week. This propellant consisted of gelatinized nitro-cellulose with the addi- tion of a stabilizer, but it contained no nitro-glycerine.

In the enemy countries the shortage of cotton supplies was met by the extensive employment of wood cellulose, paper- makers' cellulose pulp, purified by alkaline hydrolytic treat- ments, which modify the cellulose to a nearer approximation to the standard cotton cellulose.

Cellulose Acetate. The cellulose acetates are the chemical analogues of the nitrates, and a specially prepared acetone soluble acetate was extensively used in dressing the textile coverings of aeroplane wings, the treatment having an ensemble of effects, producing shrinkage of the fabric in situ, thus a taut finish, a smooth surface and the water-resistant quality obviously in- dispensable.

In England the manufacture of the product was developed by The British Cellulose Co. on the basis of the Dreyfus patents who, since 1918, have been engaged in perfecting the " Artificial Silk " based upon the acetate. This product has the external features of the cellulose-" Silks," with certain points of superiority of the ester-derivative as a chemical substance, notably the water-resistant quality and lower specific gravity. On the other hand, certain defects as a textile thread, with high costs of manufacture, keep the present production to a definitely limited scale.

Other lines of development followed more particularly under the stress of war conditions and the resulting contributions to progress are treated in the article Fibres. One section requires further men- tion here in introducing the comprehensive subject of cellulose as a dominant factor of the organic world. Recent research work has established on a basis of direct proof that cellulose is assimilated by the Herbivora and has therefore a positive value as food-stuff: a conclusion which rested previously on inferential evidence from physiological-chemical statistics. The positive flesh-forming func- tion postulates conversion of the cellulose into water-soluble de- rivative, carbo-hydrates probably, as a digestive process in which the animal secretions are operative; at the same time there are the distinctive fermentations, previously mentioned, of the celluloses to ultimate products, under bacterial action, which are known to occur in the digestive tract of the animal and of which the physi- ological value or function remains undetermined.

Such fermentations, characterized by the researches of Omeliansky and Macfadyen, in regard to " Thermophilic " bacteria, and hitherto

pure " cultures of these have however been observed as processes of long duration. The current developments of an industrial re- search syndicate, Power Spirit, Ltd. (Stockton-on-Tees and Epsom), and H. Langwell are establishing such fermentations as industrial methods for the production of acetic acid and alcohol.

Symbiotic bacterial growths at 3O-4O C. are now controlled, by the associated chemical conditions of reaction, to produce ether as main product, and to break down the celluloses in massive quan- tities in the relatively short periods which are required for starch fermentations.

In another field, which is also comprised in the vast domain of the natural history of " cellulose," researches are being actively prosecuted in elucidation of the constitution of the peat-lignite coal groups of natural products, obviously derived from, and transformation products of, " cellulose " in the inclusive sense of the term.

The Hemi-Gelluloses have a typical representative in the parenchyma of the " locust " bean, the seeds of cevatonia siliqua. On digestion with water the cellular tissue is transformed into a series of hydrated gel-products which mix with the water to pseudo-solutions of extreme specific viscosity. The products (Tragasol) find extensive application as a dressing or " finish " of textile goods and leathers. These hydrated hemi-celluloses combine with tannic acid to form characteristic precipitates which are reversible gels. The reactions and properties of these compounds are the basis of new processes of hide tanning. An expose of these methods with the rationale of principles will be found in an article " Colloidal Tannin Compounds ' (C. F. Cross and others) /. Soc. Dyers and Colourists 35 (1919). 62-8.

The Compound-Celluloses. The ligno-celluloses, represented by the typical fibre-substance of jute (bast-fibre), are the subject of a paper " Lignum Reactions and Constitution," Cross and Bevan, /. Soc. Dyers and Col. 32 (1916), giving an account of researches which establish a statistical constitutional formula for the lignine complex of which a diketohydrobenzenc and a hydro-pyrone group are characteristic ; in addition, as secondary components are ketene and methoxy groups.

The ligneous components of perennial ligno-celluloses the wood of forest trees have been further investigated by: Klason, Berl. Ber. 53 (1920), 706, 1864; Heuser and Skioldebrand, Z. Angew. Chem. 32 (1919), 41; Hagglund, Chem. Zentr. 90 (iii) (1919), 186; Honig and Fuchs, Monatsh. 40 (1919), 341.

The Cuto-Celluloses, the protective epidermal covering of plant organs, especially of the organs or parts functioning in active assimi- lation, are relatively inaccessible by reason of their minute propor- tion by weight or mass, and from the fact that they require chemical treatment more or less severe for their isolation as a separated tissue, which treatments produce considerable modifications of the parent substances. The epidermal tissue " raffia " on the other hand is separated by merely stripping from a palm leaf; being thus obtainable in massive quantity and investigated as a " parent " sub- stance, it is an attractive subject for developing this field of research. It is however a mixed tissue of which the actual epidermis constitutes about 40 % : therefore, the quantitative data resulting from investigation require inferential interpretation in regard to the latter. Recent researches establish the general character of the tissue complex as an (oxidized) cellulose ligno-cellulose ether ester with acid functions. The characteristic acid component of the ester is an unsaturated acid Ci2 H 3 2 O 3 containing I COOH and I OH group " Raffia and Cuto-cellulose " Cross and Bevan, J. Soc. Dyers and Col. 35 (1919), 70-5- (C.F. C.) '

CENSORSHIP. The World War brought about various forms of restriction of publicity in the shape of a censorship, which provides a new chapter in the history of the Press Laws (see 22.299).

(i) UNITED KINGDOM. The following note to newspaper editors, dated July 27 1914, was the first official intimation to the British press of the approach of war:

"At a meeting of the Admiralty War Office and Press Committee, held this afternoon, it was resolved that as, in view of the present situation, the authorities may have to take exceptional measures,, the Press should be asked to refrain from publishing any information relative to movements of British warships, troops, and aircraft, or to war material, fortifications, and naval and military defences, without first communicating with the Admiralty and War Office respectively in accordance with the arrangement which was noti- fied to you by me in January of last year.

" Having regard to the nature of the case it is found impossible further to indicate the character of the information the publication of which is undesirable in the national interests. The request does not affect the dissemination of news concerning ordinary routine movements or training on the part of the Navy or the Army; its object is to prevent the appearance of anything concerning steps of an exceptional kind which may be rendered necessary by the existing state of affairs.

"I may add that the authorities from time to time will continue to issue such information as may be made public."

The " Admiralty War Office and Press Committee " had been formed in 1911, mainly through the efforts of Mr. (afterwards Sir) Reginald Brade, to establish a permanent liaison in peace and war between the Admiralty and the War Office on the one hand and the Press on the other. The Committee consisted of representatives of the two departments and the London and provincial newspapers. Apart from the Official Secrets Act, no legislation existed which enabled the authorities or the Committee to suppress the publication of naval and military information. Notwithstanding this, the whole of the newspapers loyally observed the Committee's request, followed by others of a more detailed character, dated July 29 and 30 respectively. The result was that the British preparations were made with such secrecy that the Germans subsequently admitted that on Aug. 20 they knew neither when nor where the British troops were landed, nor their strength.