372 



NATURE 



[December 3, 1914 



Sunset "afterglows" resembling- those seen after 

 the memorable Krakatoa eruption were recorded on 

 various occasions during the autumn and winter of 

 1913-14. We have now received from Prof. Ignazio 

 Gain the third of a series of reports dealing briefly 

 with these observations, this report being reprinted 

 from the Atii della pontifica Accadeniia romana dei 

 nuoiii Lincei, vii., read last June. The phenomena 

 were noticed for the first time at Rome on July 13, 

 1913, and about the same time at Bagneres de 

 Bigorre, in the Pyrenees. The most noticeable dis- 

 play seems to have occurred on November 29, when 

 it was recorded in France, Italy, Belgium, and 

 England. At Rome the phenomenon was observed 

 in a greater or less marked degree from February 15 

 onwards until xA.pril 10, but while in the typical after- 

 glow the colour passes gradually from yellow through 

 orange, sometimes mauve to a deep crimson, only the 

 yellow and orange, sometimes only the yellow, were 

 observed in the western horizon at Rome towards the 

 end of this period. On the other hand, marked 

 effects were recorded by Krebs in Holstein on 

 December 31, when the moon added to the eff^ect. 

 The February glows were observed at Brussels, and 

 particularly on February 19 in Morocco, where they 

 were supposed at first to be due to an aurora borealis. 

 In China, Father Corvillard describes fine displays 

 on October 30, 1913, and April 18, 1914. Assuming 

 these effects to be due to volcanic dust, as in the case 

 of Krakatoa, Prof. Galli refers them to the eruptions 

 of Katmai, in Alaska, on June 6, 1912, Asama-Yama 

 in June 1913, Mount Benbow, in the New 

 Hebrides, on December 6, and Sakarishima, in Japan, 

 on January 11, 19 14. These eruptions, especially 

 the last, were accompanied by copious emission 

 of dust, but whether the later date observa- 

 tions, particularly the Chinese one of April 18, 

 were due to the last eruption, can scarcely be 

 decided definitely on the evidence now submitted by 

 Prof. Galli. 



An interesting paper on the presence of salicylic 

 aldehyde in soils is contributed to the Journal of the 

 Franklin Institute by Dr. Oswald Schreiner and Mr. 

 J. J. Skinner. From certain soils, especially from 

 some which had been used for intensive culture and 

 greenhouse work, marked traces of an aldehyde could 

 be extracted which showed the qualitative properties 

 of salicylic aldehyde. The aldehyde extract was found 

 to exercise a marked toxic effect on plant growth, 

 and as the proportion of aldehyde is largest in the 

 case of heavily manured greenhouse soils which have 

 become " sick," there seems to be a relationship 

 between the " sickness " and the proportion of alde- 

 hyde present. On the other hand, only a relatively 

 small number of the poor soils examined showed the 

 presence of the aldehyde, owing perhaps to the 

 presence of other toxic substances. The material ex- 

 tracted by the aldehyde method was in all cases 

 extremely small, and frequently gave no aldehyde 

 reaction, although exercising marked toxic effect. 

 What the harmful constituent in such cases is cannot 

 yet be stated. In many instances the extract was not 

 NO. 2353, VOL. 94] 



only not harmful, but exercised a stimulating effect 

 on plant growth. 



To the Popular Science Monthly for November 

 Mr. R. Hugins contributes an interesting article on 

 civilisation as a selective factor, in which it is con- 

 tended that, contrary to the view generally put for- 

 ward by writers in recent years, more particularly by 

 Weismann and Wallace, there has been a real 

 improvement of civilised man by an " agency at once 

 powerful, comprehensive, and continuous." This 

 agency may be designated the " elimination of the 

 £mti-social." The effect of this influence in modifying 

 individual and national character is traced in its many 

 forms, such as the elimination of the criminal, 

 voluntary withdrawal, including suicide, occupational 

 and geographical withdrawal, and, possibly most 

 active of all, military selection, which by eliminating 

 in the past large numbers of the predatory and in- 

 tractable members of society has had the curious 

 result that there has been an actual improvement of 

 the military value of civilised races taking place side 

 by side with the development of the moral character 

 of those races. The reason for this apparent paradox 

 is to be found in the fact that the same moral quali- 

 ties have been selected through the elimination of the 

 anti-social as are essential in the best armies — virtues 

 such as obedience, the habit of discipline, self-control, 

 and steadfastness. 



We have received a copy of a pamphlet entitled, 

 " English, French, and German Vocabulary for Water 

 Supply in the Field," prepared by Mr. Philip 

 Parker, of 25 Victoria Street, S.W., for mem- 

 bers of the expeditionary force. The pamphlet 

 contains, in addition to what is implied by 

 its title, a number of sentences in the three languages 

 well calculated to be of great use to the soldier in- 

 quiring from a foreigner with regard to water supply. 

 The words in the vocabulary, although necessarily 

 not numerous, appear to be well chosen ; the author, 

 however, is apparently not very well informed as to 

 some of the foreign equivalents of chemical terms, 

 and some of the chemical formulae are wrong. The 

 pamphlet concludes with some instructions for the dis- 

 infection of water by chloride of lime. These notes 

 are somewhat laconic and appear to supplement or 

 emphasise other instructions on the same subject. 

 The suggestions for a rough and ready method of 

 determining the quantity of chloride of lime required 

 are decidedly ingenious, but we fear that not only 

 the suggested dose, which apparently works out at 

 about three parts of active chlorine per million parts 

 of water after fifteen minutes' contact, but, more par- 

 ticularly, the time of contact (fifteen minutes) of the 

 water with the disinfectant are considerably too low 

 for safety. Probably two or three times the dose 

 with ten to fifteen hours' contact would be none too 

 much to render a polluted water reasonably safe, and 

 surely in a matter of this kind it is better to err on 

 the side of safety. Apart from this, the pamphlet 

 fulfils a very useful purpose, and we congratulate the 

 author on the service he has rendered to our troops 

 by producing it. 



