ground, the Germans lost 284,000 prisoners alone. As to economy in artillery personnel, at the third battle of Ypres 121,000 artil- lery personnel, were used on a front of 17,000 yd., the maximum penetration attained on July 31 (one day) being 3,300 yards. At Cambrai 4,100 tank personnel carried out the work normally done by the guns on a front of 13,000 yards. The maximum penetration attained in one day was 9,500 yards. .As to economy in cavalry personnel, the personnel of all ranks in a cavalry division (without the Royal Horse Artillery) would suffice to man and equip three brigades of Whippet tanks or 540 machines. As to economy in ammunition, at the battle of Arras, on a front of 17,000 yd., 2,007,534 shells, weighing 57,000 tons, were fired; at the third battle of Ypres, on the same frontage, 3,107,363 shells, weighing 93,463 tons, were fired. At Cambrai, on a 13,000 yd. front, 293,149 shells, weighing 5,824 tons, were ex- pended. It is shown that the use of tanks also leads to economy in munition manufacturing man-power, in shipping and land transport, in weight carried by the soldier, in labour on the battlefields, in property damaged, in forage or food, in time and in cost of production. In regard to the latter item the cost of projectiles and explosives alone for 1918 was 329,860,344 and for the undeveloped new arm, tanks, 9,587,960. This inevitably leads to speculation as to what results might have been had Mr. de Mole's suggestion made in 1912 been taken up and devel- oped, even at the cost of 12 hours' conduct of the war in 1918. The principle of mechanical warfare and the advantage of using power-driven machines instead of human and animal muscle having been established in one particular direction, there is little doubt but that it will be applied in others. In future, there will be larger and smaller fighting tanks developed from those born in the World War. They will be speedier, more pow- erful and have a far longer range of action. Some will also be amphibious, and all will be less easy to stop than the present somewhat embryonic machines. The principle of track propul- sion will be applied to vehicles of all types and not confined to fighting machines, and will to a great extent eliminate the neces- sity of using roads or railway, and place the movement of armies on a " two-dimensional " basis instead of being on a one-dimen- sional basis as it has in the past. Future fighting tanks will in certain theatres be able to replace cavalry and may against a civilized enemy be able to carry out, with aeroplanes, those long- distance raids against H.Q. and important points far behind the fighting-line, which since the advent of the machine-gun cavalry cannot execute, will give greater facility both for the release of gas in large quantities, if gas is used, and also for obtaining protection against gas. The fighting machines will be very largely used in conjunction with action in the air, and the two services will be complementary and mutually helpful. Large tracts of roadless country which have to be held against an uncivilized enemy, or a hostile population, will provide the first opportunities for the development of this combination, on account of the saving that will be effected in men and animals, the most expensive and delicate parts in an armed force. In killing-power, mobility, and endurance, one efficient mobile machine with its crew and machine-guns will be able to take the place of many infantry or cavalry soldiers and many horses, and will cost less to maintain and feed. In the United States the possibility of the " motorization " of all war transport and of eliminating the horse was in 1921 being fully discussed, and if the signs are read correctly this will be the general tendency, so that the great wars on land of the future will be practically horseless and conducted by far fewer men in the field and more men in the factory and workshop than has been the case in the past. Strength for war will not in the future be estimated by counting heads, for, beyond the minimum necessary, the greater the number of human beings in a force in the field the greater will be its vulnerability. The introduction of the tank in 1916 up- set all the existing values of field defences, and its natural and inevitable evolution will cause a revolution in the methods of war as great as that in tactics caused by its original appearance.
In the compilation of this article reference has been made to the following works: Clough William-Ellis and A. William-Ellis,
The Tank Corps (1919); J. F. C. Fuller, Tanks in the Great War (1920); D. G. Browne, The Tank in Action (1920); Dutil, Les' Chars d'Assaut, leur creation et leur role pendant la guerre, 1915-1918 (1919) ; M. Schwarte, Die Militdrischen lehren des Grossen Krieges (1920).
Figs. 1,9, 10 and II are from Tanks in the Great War by Col. J. F. C. Fuller, D.S.O., by permission of the author and Mr. John Murray. Figs. 2, 3, 4, 5, 6, 7 and 8, from " British Tanks " by Sir E. H. Tennyson d'Eyncourt, K.C.B., D.S.O., are reproduced on a reduced scale by permission of the publishers of Engineering, (E. D. S.)
TANNENBERG, a village of East Prussia, 10 m. S.W. of Hohenstein. It has given its name to two battles of great importance
in German history, the battle of July 15 1410, in which thei
Poles and Lithuanians destroyed the forces of the Teutonic i
Order (see 21.905), and that of Aug. 26-31 1914, in which the:
German VIII. Army under Gencral-Oberst von Hindenburg
destroyed the Russian II. Army commanded by General Samso-
nov. The latter is described in detail under the heading MASU-J
RIA, BATTLES IN. For a critical account of the former, the story
of which has been overlaid by a mass of legends, see Delbriick,
Gesch. der Kriegskunst, vol. iii., book iv., ch. 6.
TARKINGTON, [NEWTON] BOOTH (1869- ), American!
writer, was born in Indianapolis, Ind., July 29 1869. After studying at Phillips Academy, Exeter, Mass., he entered Purdue University, Lafayette, Ind., but two years later transferred to Princeton, where he graduated in 1893. At first he intended to' follow a business career, but after a few years devoted his time :
to writing. He was elected to the Indiana House of Representatives for the term 1902-3. In 1918 he received the degree of
Litt.D. from Princeton. In 1920 he was elected to the American
Academy of Arts and Letters. The same year he was engaged as
a writer of photo-plays by the Goldwyn Pictures Corporation.
His first story, The Gentleman from Indiana, was published in
1899, having appeared already as a serial in McClure's Magazine.
In 1900 his reputation was established by Monsieur Beaucaire,
which he successfully dramatized (with E. G. Sutherland) in
1901. In 1919 he was awarded the Pulitzer Prize by Columbia
University for his novel, The Magnificent Ambersons (1918).
His other stories include The Two Vanrevels (1902); Cherry (1903); The Conquest of Canaan (1905); Guest of Quesnay (1908); Beauty and the Jacobin: an Interlude of the French Revolution (1912); Penrod (1914); Penrod and Sam (1916); Ramsey Milholland (1919); Alice Adams (1921). His plays include Cameo Kirby (1907); Your Humble Servant (1908); Mister Antonio (1916); The Country Cousin (1917, with Julian Street); The Gibson Uprirhl and Up From No- where (1919, both with Harry Leon Wilson) ; Clarence (1919).
TATA, SIR RATAN (1871-1918), Parsee financier and philanthropist, was born at Bombay Jan. 20 1871, the son of the famous Parsee merchant Jamsetji Nasarwanji Tata (see 26.448). He was educated at St. Xavier's College, Bombay, and afterwards entered his father's firm. On the death of the elder Tata in 1904, Ratan Tata and his brother Dorabji Jamsetji Tata (b. 1859) inherited a very large fortune, much of which they devoted to philanthropic works of a practical nature and to the establishment of various industrial enterprises for developing the resources of India. An Indian institute of scientific and medical research was founded at Mysore in 1905, and in 1912 the Tata Iron and Steel Co. began work at Sachi, in the Central Provinces, with marked success. The most important of the Tata enterprises, however, was the storing of the water-power of the Western Ghats (1915), which provided the city of Bombay with an enormous amount of electrical power, and hence vastly increased the productive capacity of the Bombay industries. Sir Ratan Tata, who was knighted in 1916, did not confine his benefactions to India. In England, where he had a permanent residence at York House, Twickenham, he founded (1912) the Ratan Tata department of social science and administration at the London School of Economics, and in 1912 established a Ratan Tata fund at the university of London for studying the conditions of the poorer classes. He died at St. Ives, Cornwall,
Sept. 5 1918.
TAUSSIG, FRANK WILLIAM (1859- ), American econo-
mist (see 26.456), was during 1917-9 chairman of the U.S
Tariff Commission, which made a special study of commercial
