May 17, 1906] 



NA TURE 



65 



of the observations of sun-spots made by the late Dr. 

 ■C. H. Peters, extending over the period iSbo-iSyo, and 

 Including the determination of more than 13,000 helio- 

 gra[)hio positions of spots on more than iioo days; a 

 pa|)i'r by I'rof. \V. H. I'ickering on planetary inversion, 

 which the author illustrated by experiments with a gyro- 

 scope ; and an account of the foundation, and the partial 

 destruction by fire, of the Philadelphia Observatory, by 

 Prof. iM. .Snyder. 



.■■ioi.Aii Pkominunces during 1905. — The usual annual 

 smnmary of the prominence observations carried out at 

 the Catania Observatory during the past year is published 

 by Prof. Mascari in No. 4, vol. xxxv., of the ilcmorie 

 ciclla Socictii degli Spcttroscopisti Italiaiti. 



The results show that the mean daily frequency of 

 prominences observed was greater in 1905 than in 1904 

 and 1903, but the increase was not so great as might have 

 been expected. As in previous years, it is seen thai the 

 increase in mean daily frequency corresponds with a de- 

 irease in heliographic latitude. In 1904 the mean daily 

 frequency was 2 90 and the mean latitude 3()°'6, whilst for 

 1905 the corresponding figures were 3-05 and 30°-8. The 

 mean altitude of the prominences during 1904 was 43"-7, 

 and in 1005 it was 44"i ; the corresponding extensions of 

 the prominences along the solar limb were 7°-27 and 8°-y~. 



The greater frequency of prominences in the sun's 

 northern hemisphere still persists, the values for 1905 being 

 I 77 for the northern and 1-28 for the southern hemisphere. 



The Period of /3 Lvr.«. — Referring to the recent note 

 by Mr. Roberts on the increasing period of (3 Lyrce, Prof. 

 Schaeberle suggests another possible cause which may 

 account for that phenomenon. 



It is now generally accepted that incandescent bodies 

 have the power of repelling fine particles of their com- 

 ponent matter to great distances, and Prof. Schaeberle 

 suggests that, at a certain stage in the life-history of such 

 a body, the decrease in mass may be so rapid as to cause 

 an increase in the periodic time of any other body belong- 

 ing to the system. If part of the ejected mass afterwards 

 returns to the parent body other changes will obviously 

 ■occur (Observatory, No. 370). 



THK SIXTH INTERNATIONAL CONGRESS 

 OF APPLIED CHEMISTRY. 

 ■yxniEN the International Congress of Applied Chemistry, 

 ' ' assembled at Berlin in 1903, chose Rome as its next 

 meeting-place, the fear was expressed by some that the 

 Italian chemical industry might not perhaps be of sufficient 

 magnitude to ensure a large attendance at the next con- 

 gress. The brilliant success of the meeting which has 

 just terminated has shown, however, that these fears were 

 entirely without justification, and the number of important 

 communications from the Italian members of the congress 

 proves the reality of the progress which Italy has made of 

 late years in chemical industry. 



The meeting was opened on .\pril 26 under the most 

 favourable auspices by the King and Queen in person, 

 accompanied by the Minister of Public Instruction and other 

 liigh officials. The place of meeting was the magnificent 

 Palace of Justice, then brought into use for the first 

 time ; in fact, it is not yet wholly completed as regards the 

 internal decorations. There being a large number of rooms 

 in the building, space was easily found for the sixteen 

 sections into which the congress was compelled to sub- 

 divide itself. The number of British members was more 

 than thirty, and on the whole the attendance from other 

 countries was very satisfactory, even China being repre- 

 sented. It is somewhat of a novelty to hear speeches in 

 Chinese at European scientific meetings, and shows that 

 the awakening of the Celestial Empire is becoming an 

 accomplished fact. Such a congress is an interesting study 

 in ethnology as well as philology. Officially only four 

 languages are supposed to be used, namely, English, 

 French, German, and Italian ; but the greatest leniency 

 is shown in this respect, and the reporters must sometimes I 

 rely on summaries made by the speakers themselves. 



Among the papers read before the full meeting of the 

 congress the most important was undoubtedly Dr.' .Adolph 

 Frank's description of his process for the direct utilisation 



NO. 1907, VOL. 74] 



of the nitrogen of the atmosphere for the production of 

 artificial manure and other chemical products. Dr. Frank's 

 invention is not only ingenious, but its effects on the 

 future of the human race will probably be of the greatest 

 importance. The inventor is a veteran in agricultural 

 chemistry ; he it was who, more than fifty years ago, intro- 

 duced the potash salts of Stassfurt to the notice of agri- 

 culturists. Now nearly three million tons of these salts 

 are used annually by agriculturists all over the world. The 

 problem of the fixation of atmospheric nitrogen has often 

 been attacked, for the first time on a large scale during 

 the French Revolution, .^t that time France, surrounded 

 by her enemies, was cut off from the supply of saltpetre 

 necessary for national defence. A committee of French 

 chemists then established the saltpetre farms where the 

 nitrifying organisms, w-ilh which we have since become 

 more intimately acquainted, produced the necessary means 

 of defence. We in Great Britain, however, are still entirely 

 dependent upon foreign sources for the explosives necessary 

 for our national defence, and it is only by the establish- 

 ment of some such process as Dr. Frank's in Great Britain 

 that we shall place ourselves in safely in this respect. 

 The invention is not a complicated one, the difficulties 

 consisting chiefly in the solution of new problems of 

 chemical engineering. Calcium carbide is first produced 

 and then heated wilh nitrogen obtained by the fractional 

 distillation of liquid air. During this distillation oxygen 

 is obtained as a by-product, and may be utilised for the 

 production of nitric acid from ammonia, which, again, is 

 one of the substances produced by Dr. Frank. The first 

 raw material obtained is calcium cyanamide, and it is this 

 that is used as a nitrogenous manure, numerous experi- 

 ments having shown that the nitrogen which it contains 

 can be easily assimilated by plants. For countries such as 

 Italy, and more especially India, wMth large agricultural 

 populations who do not possess sufficient cattle to supply 

 the requisite nitrogenous manure, this direct utilisation of 

 the inexhaustible nitrogen of the atmosphere cannot fail 

 to be of enormous importance ; but to the chemist the 

 calcium cyanamide has other attractions. From it have 

 been produced, not only ammonia and nitric acid, but also 

 urea and guanidinc. \Ve are therefore on the high road 

 towards the artificial production of the alkaloids, and the 

 next step will probably be the building up of substances 

 directly assimilable by human beings, in other words, 

 artificial foods. 



But while chemists revelled in these anticipations they 

 did not forget more practical subjects. An excellent paper 

 by Sir William Ramsay gave a clear and exhaustive 

 account of the present state of the sew'age question in 

 Great Britain. Special attention was given by the author 

 to the bacterial methods of sewage disposal which are 

 now being so widely adopted. M. Moissan, whose work 

 with the electric furnace is so well known, gave the results 

 of his experiments on the distillation of metals. All metals, 

 indeed all substances, are volatile at a temperature below 

 3500° C, therefore M. Moissan draws the conclusion that 

 the temperature of the sun cannot exceed this ; it must, 

 indeed, be somewhat less, as the bulk of the elements of 

 which it consists are volatile at a lower temperature than 

 the maximum mentioned. No doubt the data with which 

 Prof. Moissan has furnished chemists will be utilised for 

 practical purposes, especially in the purification of metals. 



Manv of the papers read before the various sections con- 

 tained matter of great scientific interest. The report of 

 the International Committee on the Unification of Analytical 

 Methods was presented by X)r. Lunge, and will be of greal 

 assistance to analysts in different countries who wish 10 

 secure uniform results. Prof. W. N. Hartley's paper on 

 the use of the spectrograph in analysis aroused much 

 interest in the photographic section. It is certainly a 

 great advantage to be able to make a quantitative analysis 

 of a rare object in metal without defacing it in any way, 

 and the convenience of the method will no doubt ensure it 

 general acceptance when it becomes better known, .\nother 

 communication made to the inorganic chemistry section 

 was of interest, inasmuch as it holds out hopes of a con- 

 siderable reduction in the price of photographic and olher 

 glass of high quality. Hitherto such glass has been made 

 in the expensive pot furnaces, but the author of the paper, 

 Herr F. Heller, slates that he has succeeded in making 



