656 



NATURE 



[February io, 191 6 



upon, the mysterious dental disease known as pyorrhoea. 

 At all the meetings a special feature will be made of 

 the technical methods to be employed with the view of 

 showing the obtained results in the highest perfection 

 which the progress of scientific microscope construction 

 Tias rendered possible. 



In the January number of Science Progress Dr. 

 F. A. Mason gives a second instalment of his article on 

 the influence of research on the development of the 

 coal-tar dye industry. This deals first with the syn- 

 thesis of substantive dyes, and then with the technical 

 production of indigo, the new vat dyes, and the sulphur 

 colours. A very interesting account is given of the 

 indigo problem. " In 1880 a step was taken which 

 could only have happened in Germany, and where the 

 boards of directors were composed largely of able and 

 far-seeing chemists : the two great firms of the 

 Badische Company at Ludwigshafen and Meister, 

 Lucius, und Briining at Hoechst joined forces in order 

 to attack the problem systematically, and entered into 

 an agreement to carry on researches conjointly, shar- 

 ing profits and results." It was only after nearly 

 twenty years that the problem was solved, and then the 

 solution came as the result of an accident; it is now 

 well known that the commercial success of the manu- 

 facture of indigo had its origin in the accidental break- 

 ing of a thermometer in the naphthalene undergoing 

 oxidation to phthalic acid by strong sulphuric acid. 

 The presence of a trace of mercury acting as a cata- 

 lyst, and so enormously improving the yield of phthalic 

 acid, made possible the artificial productions of indigo 

 at a remunerative price, and led to the gradual ex- 

 tinction of the native industry, which formerly was 

 valued at four or five millions sterling. The interest- 

 ing later competition between the naphthalene process 

 and the phenylglycine process is dealt with, as well 

 as the connection between this industry and the 

 development of processes of making liquid chlorine, 

 hydrogen, and synthetic nitrates, which have played so 

 important a part in the present war. 



Whether the differences in the choice of food ex- 

 hibited by the crossbill in Ireland are to be attributed 

 to tastes formed by these immigrants in separate 

 centres of dispersal is discussed by Mr. C. B. Moffat 

 in the Irish Naturalist for January. The birds which 

 effected a settlement after the invasion of 1888 showed 

 a decided preference for the cones of the larch, while 

 those which formed part of the invasion of 1909 chose 

 rather the cones of the Scotch fir. Observations made 

 during the summer of 1915 showed that while larch 

 cones were abundant they were comparatively neglected 

 in favour of the Scotch fir. The author also casts doubt 

 on the generally accepted belief that the cones, of the 

 Spruce fir form the staple food of the common cross- 

 bill, in the Continental parts of its range, those of the 

 Scotch fir being exclusively eaten by the larger parrot 

 crossbill. 



From the annual report of the Department of Agri- 

 culture, Nyasaland, we learn that the extension of 

 tea-growing in the Mlanje district is very satisfactory 

 and that good prices have been realised. Cotton 

 is still the most extensive cultivation in the Protec- 

 torate, but the commercial cultivation of Egyptian 

 NO. 2415, VOL. 96] 



cotton has now ceased after exhaustive trials, 

 the type compared with Nyasaland Upland proving 

 unprofitable, probably owing to its sensitiveness to 

 climatic variations and to its susceptibility to bacterial 

 blight. The total acreage under cultivation in the 

 Protectorate is a good deal less than that reported in the 

 previous year, largely due to the abandonment of Ceara 

 rubber and to the sad loss of several of the younger 

 planters in the defence of Karonga. Afforestation at 

 Zomba and Mlanje with the native Mlanje cypress 

 {Widringtonia Whytei) is being continued, and the 

 extensive Eucalyptus plantations near Zomba and 

 Blantyre have made remarkable growth. This tree is 

 undoubtedly destined to be the fuel tree of Nyasaland. 



A GREAT deal of useful information about Egypt is 

 contained in the Egyptian Government Almanac for 

 1916 (Cairo : Government Press), a small paper-covered 

 volume costing one shilling. It is, in fact, an epitome 

 of the geography, commerce, industries, Government 

 and public services of the country. There is even a list 

 of the Government publications, the only omission in 

 which is a summary of the maps published by the 

 survey department. There is, however, a short article 

 dealing with the work of the survey. 



A MAP of South and Central Africa on a scale of 

 I to 5,000,000 has just been published by Bartholomew. 

 The coast from Dar-es-Salaam to Mombasa is shown 

 in an inset on an enlarged scale, as are also the prin- 

 cipal ports. We notice that South- West Africa is out- 

 lined in red, and the colouring of German East Africa 

 and the Cameroons may be considered transitional, as 

 the brown colour appears only as a border. The map 

 is finely executed and clear, and should be useful in 

 following the forthcoming operations against the Ger- 

 mans in East Africa. There are one or two corrections 

 in the railways needed. Upington and Warmbad are 

 now linked by rail — an important factor in General 

 Botha's subjugation of South-West Africa. The map 

 is sold at half a crown. 



In the course of a lecture on the romance of the 

 Indian Surveys (Journal of the Royal Society of Arts, 

 January 21) Sir Thomas H. Holdich commented on the 

 policy that the Indian Government had shown with 

 regard to frontier exploration since the war with 

 Afghanistan. Up to that time a good deal had been 

 done by individual effort, whjch was then discouraged, 

 if not forbidden, by Government. While the discoun- 

 tenance of iri-esponsible travellers may be necessary in 

 the interests of the peace and security of the frontier, it 

 is a policy that cuts two ways. Undoubtedly it has 

 curtailed the possibilities of seizing on favourable 

 opportunities for securing geographical knowledge. 

 For half a century we learnt nothing of the wild border 

 hills fringing the great plateau of Afghanistan and 

 Baluchistan, or of further Kashmir, or the great 

 Tibetan tableland, all of which, from a military point 

 of view, it was essential we should know. Sir Thomas 

 Holdich contrasted this policy with that pursued by 

 Russia during the same period, or that which would 

 most certainly have been pursued by Germany had she 

 been in our place, and he doubts whether the excessive 

 caution of our Government was not misplaced. 



