NOTES A99 



experiment he has made concerning the constitution of the terrestrial atmosphere. 

 Photographed from the ground, or even from a mountain-top, the solar spectrum 

 does not extend beyond \2,c.oo, and the absorption of the shorter wave-lengths has 

 been shown to be almost certainly due to ozone. Prof. Strutt has now photographed 

 the spectrum of a mercury vapour-lamp 4 miles distant, and finds that it extends 

 at least as far as ^2,536, a line near the maximum intensity of the ozone absorption 

 band, so that in this case ozone cannot be responsible for the shortening of the 

 spectrum. It is therefore necessary to conclude that ozone is much more abundant 

 at higher levels than at the earth's surface, a result which is in agreement with 

 certain chemical determinations of atmospheric ozone. 



In the Proceedings of the U.S. National Museum, Washington (pp. 553-63, 

 1917), Messrs. T. L. Watson and R. E. Beard give an account of some experi- 

 ments they have made on the chemical composition and physical structure of 

 variously coloured varieties of quartz. One interesting case discussed is that of 

 the amethyst. They find that it contains more manganese than any other variety 

 of quartz they examined, and conclude that the colour is mainly due to colloidal 

 particles of manganese oxide of ultra-microscopic dimensions. The colour of rose 

 quartz when destroyed by heat cannot be restored by daylight or exposure to 

 radium, and is probably not due to any inorganic substance. 



Some interesting details of the Haber process used in Germany for the 

 synthetic production of ammonia are given by Dr. C. L. Parsons in a report to 

 the U.S. Government on the processes of nitrogen fixation {Jour. Soc. Chem. Ind. 

 October 31, 1917). This process is worked on a huge scale by the Badische 

 Company, the 1917 output being equivalent to over 500,000 tons of ammonium 

 sulphate, as against 20,000 in 1913. The operations required, however, involve 

 some danger and much technical difficulty, since the nitrogen and hydrogen are 

 combined at a temperature above 500 C. and at pressures from 125-150 atmo- 

 spheres. Indeed, the process involves so high a degree of training that it is 

 reported that if the present technical staff were lost many months would be 

 required to train another. The process, which is very cheap, has not yet been 

 worked successfully outside Germany in spite of the urgent necessity to find some 

 source of nitrates other than the Chile deposits. The General Chemical Co. 

 has, however, achieved success in causing the combination of hydrogen and 

 nitrogen at lower pressures than those demanded by Haber's process. Their 

 process has been offered to the U.S. Government. It is probable that in the 

 future both processes will find a strong competitor in the cyanide process which, 

 while presenting no special difficulties, has not yet been worked out to the point 

 where factory construction can begin. 



The report of the Committee appointed to consider the scheme of examination 

 for Class I of the Civil Service Examination deserves serious consideration. It 

 is proposed that, in future, the examination should be divided into two sections, 

 the first, a compulsory one, having a maximum of 800 marks, and the second, 

 containing the optional subjects, a maximum of 2,000, with an extra 100 for an 

 additional modern language. The first section includes a paper on contemporary, 

 social, economic, and political questions ; another on the general principles of 

 science ; and a third on translation from a modern language. These, together 

 with two papers on English, each gain 100 marks. There is, however, a viva voce 

 examination on matters of general interest which receives no fewer than 300 marks. 

 This is a very large proportion of the whole, and while permitting the examiners 

 to test the candidates' personality, throws upon them rather a heavy responsibility. 

 The second section is noteworthy as giving equal weight to classics, mathematics, 



