July ii, 1918] 



NATURE 



Z77 



of Poccilopsis with wingless females are given. Mr. 

 Harrison lays stress on the importance of these results 

 is affording evidence of the relationships between the 

 -pecies. Another paper on hybrid Lepidoptera worthy 

 if attention is that by Mrs. Merritt Hawkes (/oHfnaZ <?/ 

 Genetics, vol. vii., No. 2) on inheritance in the cross 

 of two Saturniid moths, Philosamia ricini and P. 

 cynthia, in which special attention is paid to larval 

 characters, such as spots and tubercles ; the appearance 

 of abnormal larvae with reduced tubercles (a recessive 

 character) in the Fj generation is especially interesting 

 in relation to the existence of a few Saturniid species 

 the larvae of which are always without tubercles. 



Among papers dealing particularly with problems of 

 MentU^ian analysis, R. K. Nabours and A. VV. Bel- 

 i.tmy's "Studies of Inheritance and Evolution in 

 Orthoptera" [Joumc^ of Genetics, vol. vii.. No. 1) 

 -;ive a vast amount of detail of experimental work on 

 grasshoppers of the Tettix group. The most important 

 theoretical result is the apparent demonstration that 

 while some patterns are allelomorphic to each of a 

 number of others, a certain melanic pattern may be 

 allelomorphic only to its aljsence. In connection with 

 •^his subject attention must be directed to H. Terao's 

 hort but important paper on " Reversible Transform- 

 lijjlity of -Mlelomorphs " (Amer. Nat., vol. li., 

 No. 610), in which he describes cases of the occasional 

 presence of a dominant character in the corresponding 

 recessive homozygote in cultures of the rice plant. 

 The frequency of this abnormal phenomenon is studied, 

 and the author states that " the dominant and recessive 

 types concerned are assumed to be transformed by 

 certain unknown causes into the other allelomorph." 

 He then proceeds to argue that on this view it is 

 impossible to accept the theory that " the dominant 

 allelomorph is due to the real presence of a hereditary 

 material unit wjiich is absent in the recessive allelo- 

 morph," and that the two "may be supposed to repre- 

 sent two alternative conditions or phases of a single 

 hereditary substance, somewhat resembling the chem- 

 ical conception of polymerisation." 



In a controversial and stimulating " anti-vitalistic " 

 <liscussion of biological enigmas, Dr. L. T. Troland 

 (Amer. Nat., vol. li.. No. 606) carries the concepts of 

 the chemist far more intimately into life-problems, and 

 makes bold to write : " On the supposition that the 

 actual Mendelian factors are enzymes nearly all . . . 

 general difficulties instantly vanish, and I am not 

 acquainted with any evidence which is inconsistent 

 with this supposition." 



The claims of some extreme "geneticists" that no 



discussions on evolutionary problems not founded on 



"experimental evidence" can be profitable are trench- 



iitly dealt with by Dr. W. K. Gregory in an article 



ntitled "Genetics versus Palaeontology" (Amer. Nat., 



vo\. ]\., No. 6to). To manv who believe that much 



may still be done in the elucidation of phylogenetic 



problems on a large scale from the study of cfassifica- 



ion and morphology. Dr. Qregory's illustrations and 



arguments, drawn mainly from the wonderful series 



of American fossil mammals, furnish a bracing 



; f-miniscence of vouthful davs of controversv. 



G. H. C. 



THE FUTURE OF PURE AND APPLIED 



CHEMISTRY.^ 

 "pOR three years past pure chemical research has 

 ■*■ been dormant the whole world over, and it would 

 be difficult for the most accomplished essayist to arrest 

 your attention for an hour by an address on a subject 

 of purely academic interest. Our mental point of view 



1 Abridged from the presidential address delivered at the annual p^neral 

 meeting of the Chemical Society on March 21 by Prof. W. J. Pope, F.R.S. 



: and our outlook upon both present and future are 

 entirely different from those of four years ago; 

 although the present is obscure and painful, the future 

 gives promise of brilliant and rapid developments in 



; natural science in general and in chemistry in par- 

 ticular. In this belief I venture to lay before you 

 some reflections upon the growing recognition of the 

 importance of our science and upon the responsibilities 



, with which, owing to this change in public opinion, 



] our shoulders are laden. 



I I have often heard the statement made by men who 

 have grown old in the service of science that 



\ chemistry, and particularly applied organic chemistry, 

 is a subject in which the British nation can never 



; excel : that minute attention to detail, coupled with 

 the power of organisation and co-operation, entails 

 something antipathetic to the British character ; the 



j Germans, we know, have often expressed this view. 



I The events of the last three years have sufficed to 

 dissipate this fallacy for ever. The manner in which 



j Great Britain, caught in the autumn of 1914 with 

 scarcely any resources in the shape of equipment for 

 the manufacture of fine organic chemicals, has rapidly 

 become a larger producer of explosive, pharmaceutical, 

 photographic, and other essential chemicals _ than 

 Germany will remain an enigma to the historian of 



\ these present times. The obscurity which surrounds 

 this rapidly executed operation is not diminished by 

 the existence of difficulties which have naturally acted 

 as inhibiting agents. This country enjoys in a greater 

 measure than any other State a representative Govern- 

 ment ; in spite of the many advantages of such a form 

 of Government, the fact remains that it necessarily 

 admits of no representation of any phase of public 

 opinion which is not loudly and insistentlv expressed. 

 Science has always been in this latter position; it has 

 been unvocative. During the first few years of the 

 nineteenth centurv Dalton enunciated the atomic 

 theory, Thomas Young stated the undulatory theory 

 of light, and James Watt's steam engine came into 

 general use. Bv these events all the amenities of 

 human life have been revolutionised; indeed, they 

 have exercised vastlv more influence on the well-being 

 of our race than did the Napoleonic wars. So accus- 

 tomed are we, however, to routine habits of thought 

 that most of us would probably answer, in reply to a 

 suddenly posed question, that the battle of Trafalgar 

 was the most pregnant event of the first quarter of 

 the nineteenth century. 



A brief moment of reflection would lead us to correct 

 this hastv statement. Sodium was discovered by Davy 

 in 1807, and benzene bv Faraday in 1823. From 

 sodium we obtain sodamidq, the prime agent in 

 making artificial indigo an economic possibility; the 

 separation of benzene from coal-tar led by logical 

 sequence to the production of Perkin's mauve and of 

 thousands of other synthetic colouring matters, and 

 to the manufacture from coal-tar anthracene of syn- 

 thetic alizarin, the first heavy blow aimed at the posi- 

 tion of the Turkish Empire, involving as it did the 

 ruin of the Turkev-red or madder industrv. The first 

 practical orocess for making aluminium depended on 

 the use of Daw's sodium, and with the aid of Davy's 

 safetv lamn 250,000,000 tons of coal are mined annu- 

 ally in this countrv with comparatively slight risk. 

 Faradav's earlv investigations on the chemical aspects 

 of electrolysis and his studies on magnetic induction 

 led immediately to the invention of the dynamo, and, 

 through Clerk Maxwell to the ir\troduction of wireless 

 telegraphy; this one branch of Faraday's investiga- 

 tions, in point of fact, constitutes the ground-work of 

 the whole stupendous vista of results of the general 

 introduction of the electric current into modern life 

 which is so familiar to us all. Cavendish's early pro- 



NO. 2541, VOL. lOl] 



