December 8, 1898J 



NA TURE 



127 



Here, in tropical Queensland, I was much troubled by various 

 borers, and " silver-fish " ; but for the latter, which apparently 

 only devour the glaze on paper, and paste, I found a new remedy 

 in adding alum to paste, and keeping glazed writing paper in tin 

 boxes. 



For the former a solution of corrosive siiHimate and thymol in 

 alcohol, appears to be an effectual remedy, though probably it 

 would require to be re-applied from time to time ; but certainly 

 all books dressed by me with this solution inside and outside the 

 covers, have never been touched since. 



The newspaper extract (paper and date unknown), from which 

 I obtained the information, read as follows : — " Surgeon-General 

 Bidie, in the Fishing Gazette, recommends a solution of corrosive 

 sublimate and thymol as a perfect protection for books from the 

 ravages of bookworms and other insect pests, having tested it in 

 tropical countries where the termite and the larvae of innumer- 

 able creatures batten upon everything eatable, from door-posts to 

 bottle corks." 



I have certainly found this remedy thoroughly efficacious, and 

 think it deserves to be more widely known. 



J. EWEN DAVinSON. 



Branscombe, Mackay, Queensland, October 20. 



The Properties of Liquid Mixtures. 



In the abstract of my communication to the Physical Society 

 in connection with Mr. R. A. Lehfeldt's paper on the above 

 subject (Nature, December i, p. 116), the most probable 

 explanation of the fact that, when American petroleum is 

 distilled, the benzene comes over at about 65° instead of 80°, is 

 stated to be that " benzene and hexane behave, as regards 

 ■distillation, like iiiiscihle liquids."' This should read ^^ like 

 partially iiiiscible liquids."' 



The two liquids are, in fact, miscible in all proportions, and 

 the point is that, in certain respects, they behave as though 

 they were only partially miscible. Sydney Young. 



December 6. 



The Mildness of the Season. 



As an instance of the mildness of the season, I may state that 

 •on Sunday, November 27, I gathered five ripe strawberries out 

 ■of my kitchen garden ; and that a considerable number of straw- 

 berry plants still show signs of flower. Moreover, the leaves of 

 several deciduous trees, such as peaches, lilacs, Slc. , which are 

 planted in sheltered situations, are still perfectly green ; whilst 

 many others are only just beginning to assume their autumn 

 tints. I have also gathered several rosebuds this morning. 



In this part of England all the leaves have usually fallen by 

 the end of November. In fact, in ordinary seasons, the elms 

 (which shed their leaves late) are quite leafless by the middle of 

 the month. A. B. Basset. 



Fledborough Hall, Holyport, Berks, November 29. 



Iridescent Clouds. 



There was a fine example of clouds showing iridescence on 

 December 4, from 8.50 to 9.5 a.m., in the south-eastern sky. 

 It occurred on a large white cumulo-maculo cloud, the iridescence 

 being confined to the upper and lower margins, which were much 

 striated. 



This was at first the same period after sunrise as I have com- 

 imonly observed the phenomenon to occur before sunset, i.e. at 

 about an hotir's distance from each event (vide my letter on 

 the subject, Nature, vol. Iviii., p. 390). I have not seen it 

 before in the morning. E. Armitage, 



Dadnor, Herefordshire, December 5. 



The Origin of the Aurora Spectrum. 



With reference to the question as to whether there is any 

 auroral line in the position of the krypton line about 587, the 

 nearest lines to this that have been observed in the aurora 

 ■appear to be 5765 and 595 observed by Gyllenskiold. His 

 observations were only rough, but the question is whether they 

 are near enough to the krypton line for either of them to be the 

 same as it. If there is any auroral line about 556, it is likely 

 ;that the great brilliancy of that at 557 would account for its not 

 having been seen. T. W. Backhouse. 



West Hendon House, Sunderland, November 30. 



NO 15 19, VOL. 59] 



SVEN HEDIN'S ''THROUGH AS/A."^ 

 r^APTAIN FRANK YOUNGHUSBAND prefaced 

 ^ his charming work on Central Asia " In the Heart 

 of a Continent," by a lament that his early education had 

 been wasted on dead languages, so that he started on 

 his travels ignorant of scientific methods of thought or 

 observation (see Nature, June 1 1, 1896). Dr. Sven Hedin 

 has no such fault to find with his upbringing. Trained 

 in physical geography in the University of Berlin under 

 the great Asiatic traveller Baron von Richthofen, he chose 

 the least-known parts of Asia as a field for exploration, 

 and fitted himself as an explorer by years of preliminary 

 study and Eastern travel. Few men, especially in this 

 country, attracted instinctively to the studies which can 

 make them geographers, have had the opportunity of 

 becoming travellers, although many travellers have been 

 stimulated by their experiences to take up the study 

 of geography. Dr. Hedin writes, as he travelled, like 

 an accomplished geographer. He was no sportsman ; 

 and, although a sedulous collector, he was neither 

 botanist, zoologist nor geologist, possessing only that 

 sympathetic general knowledge of natural science 

 which is essential to a geographer, and invaluable to 

 a traveller as a guide to observation. He not only 

 qualified himself in practical astronomy and survey- 

 ing, so as to collect trustworthy material for maps, but 

 took special pains to master all necessary languages. 

 Besides his native Swedish he was proficient in German, 

 French, Russian and English, and could thus converse 

 easily with every European traveller and official he met ; 

 he had already learned Turki, so that in western Central 

 Asia he could question the natives directly, and in the 

 course of the journey he acquired sufficient facility in the 

 use of Mongol and Chinese to enable him to dispense with 

 interpreters. 



Being a translation, though a good one, " Through 

 Asia " cannot be compared in style with the Isest English 

 books of travel ; but in substance it is so full, solid and 

 interesting that this is soon forgotten. An awkward 

 phrase, indeed, puzzles one occasionally, such as 

 "diopters" (which may mean the sights for a plane- 

 table); " temporal observations," instead of "observations 

 for time" ; and a few others. The word "glen" is very 

 frequently used in a sense which appears to be the same 

 as valley, but may contain some undesignated shade of 

 difference. 



King Oscar, whose interest in travel and in all matters 

 Oriental is well known, interested hiinself in the proposed 

 journey, and assisted in supplying the very modest funds 

 (1900/.) required for what has turned out to be one of the 

 cheapest, as well as one of the best, of the great journeys 

 of the century. 



Dr. Hedin travelled altogether 14,600 miles, of which 

 2020 had never before been traversed by a European. He 

 made a continuous map of his route for 6520 miles, which 

 is now being worked up in the great cartographical estab- 

 lishment of Perthes in Gotha, and innumerable observ- 

 ations on the volume of rivers, the depths of lakes and the 

 temperature of air, water and soil, which will all be dis- 

 cussed and published separately. H is collections of natural 

 history specimens and archaeological remains will also be 

 made the subject of monographs. Thus although the 

 mass of the scientific data obtained is large, but little of 

 it is considered in this book, which is a compressed nar- 

 rative of the whole three years' journey, containing, in- 

 deed, a fair amount of adventure quietly told, and just 

 enough of the more technical aspect of geography to 

 enable the general reader to understand the explorer's 

 motives and appreciate his results. Enough is stated, 

 however, to show that it is the record of one of the finest 

 scientific journeys ever carried out in trackless Asia. 



1 " Through Asia," by Sven Hedin. With nearly three hundreti illustra- 

 tions from sketches and photographs by the author. Two vols. Pp. xx 

 + 1278. (London : Methuen andCo., 1898 ) 



