1 66 



NATURE 



[August ii, 1910 



some other phase of motion like the large waves. This 

 is closely examined, and observations previously made 

 upon this point 'are brought more closely in accord. 



Disturbances of magnetic needles at the time of 

 the earthquake have not been overlooked. Much is 

 said in favour of damping pendulums, and reference 

 is made to the recently devised "dead-beat" instru- 

 ments of Prince Gahtzin. We have not, however, come 

 across any reference to his method of determining the 

 direction of an earthquake from the first of the pre- 

 liminary tremors. The monograph closes with the 

 theory of the seismograph. In this we notice the 

 statement that the instruments designed by myself in 

 1892 and Dr. Schlatter about 1903, to show tilting of 

 the ground at the time of an earthquake failed to 

 show such a phenomenon. This is only true for the 

 latter instrument (see British Association Report, 

 1893, p. 222). 



Prof. Reid's memoir is a valuable contribution to 

 the mechanics of earthquakes. He has ploughed both 

 new ground and old, and seismologists will thank 

 him for the material he has furnished for their con- 

 sideration. John Milne. 



TAR, ACID, AND ALKALI. 



(i) Coal Tar and Ammonia. By Prof. George Lunge. 

 Fourth and enlarged edition. Part i., pp. xix + 563; 

 part ii., pp. xiii + 564-1 178. (London : Gurney and 

 Jackson, 1909.) Price 425. net, two vols. 



(2) The Manufacture of Sulphuric .icid and .Alkali, 

 with the Collateral Branches : a Theoretical and 

 Practical Treatise. Third edition, enlarged. By 

 Prof. George Lunge. Vol. ii., part i.. Sulphate of 

 Soda, Hydrochloric Acid, Leblanc Soda, pp. xx-i- 

 490; vol. ii., part ii., ditto, pp. xii + 491-1010. 

 (London : Gurney and Jackson, 1909.) Price 42s. 

 net, two parts. 



THESE three terms — tar, acid, and alkali — stand 

 for the most important of the determining factors 

 of chemical technology. Round them may be ranged 

 practically everything that relates to the business of 

 applied chemistry. In its most comprehensive sense, 

 each in turn may be regarded as the parent or genital 

 substance from wliich flows a countless number of 

 bodies, forming by their mutual actions and re- 

 actions the vast array of products which modern 

 manufacturing chemistry has placed at the service of 

 mankind. In the works before us. Dr. Lunge's treat- 

 ment of these themes is worthy of their importance. 

 The works themselves have already taken an assured 

 position in the literature of chemical technology. In 

 each successive edition their veteran author strives to 

 make them a faithful and adequate reflection of the 

 state of contemporary knowledge and achievement, 

 thereby tending, so long as his ministering care is 

 available, to make that position secure. They have 

 long been recognised as indispensable to the technolo- 

 gist, and each new issue is certain of an immediate 

 welcome. 



The volume on coal-tar and ammonia is now in 

 its fourth edition. What enormous changes have 

 come over the industry of tar production, and of the 

 NO. 2128, VOL. 84] 



extraction and utilisation of the innumerable sub- 

 stances which enter into its composition, will be 

 evident from even the most superficial examination of 

 the several issues. The rate of progress, indeed, 

 transcends anything to be observed in any other 

 branch of manufacture. Only nine years have elapsed 

 since the third edition made its appearance, but such 

 has been the accumulation of new material in that 

 interval that practically the whole of the chapters — 

 eleven in number — dealing with coal-tar and its pro- 

 ducts have had to be revised and in great part re- 

 written. In this section of the work Dr. Lunge 

 has had the assistance of Dr. Kraemer, of Berlin, an 

 acknowledged authority in this branch of chemical 

 technology. 



England is still the great tar-producing country of 

 the world, but her supremacy in this respect is 

 threatened by the United States. Tar is mainly 

 obtained from gas-works, from blast furnaces, and 

 from coke-ovens. In the United Kingdom the annual 

 production at the present time approaches a million 

 tons — obtained by the destructive distillation of 

 about seventeen or eighteen million tons of coal — an 

 amount exceeding that of the whole of Europe put 

 together, and probably more than twice the aggregate 

 yield of Germany and France. This country, where 

 benzene was discovered by Faraday, where its indus- 

 trial extraction was worked out by Mansfield, and 

 where the first aniline colour was made by Perkin, 

 has become simply as the hewer of wood and the 

 drawer of water in this matter. We make the tar, 

 but apparently we can do little with it except sell it 

 to the Germans in order that they shall turn it into 

 that astonishing array of manufactured products 

 which their admirable system of scientific training 

 has taught them how to produce. When in the hour 

 of her humiliation Germany set herself to reconstruct 

 the educational system which has culminated in her 

 present scheme, she forged the most powerful instru- 

 ment of national development which human fore- 

 thought could have devised. With it has come her 

 extraordinary commercial development and her ambi- 

 tion to be supreme in the world's markets, and with 

 it, too, she thinks, has come the necessity of being 

 able to protect that commerce, if necessary, by force 

 of arms. What becomes of coal-tar may seem a small 

 matter in determining the course and destiny of 

 nations. But is is absolutely certain that if 

 our university system had been developed, even 

 pari passti with that of Germany, and that if 

 those who were responsible for the government of this 

 country, and those who seek to form public opinion, 

 had paid more heed to the signs of the times, we 

 should to-day have less talk about Tariff Reform and 

 of the imperative necessity of more " Dreadnoughts." 

 If Peace has her victories, no less renowned than 

 those of War, we may well ask ourselves if we have 

 always gone the right way to work to secure the 

 victories of peace. 



Dr. Lunge's second work — that on sulphuric acid 

 and alkali, now in its third edition — further serves to 

 illustrate the same text. If there was one chemic&l 

 industrv more than another in which Great Britain 



