626 



NA TURE 



[May 13, 1922 



Government, and no foreign periodicals (except 

 German) were admitted. Inorganic chemistry had 

 no tradition until 1877, when Brauner showed 

 the aims of modern inorganic chemistry : chemical 

 (and later physico-chemical) investigations of ele- 

 ments with regard to their position in Mendelejew's 

 Periodic System. A series of results obtained was 

 published in the Trans. Chem. Soc. Lond. since 1881. 

 During the war Brauner published a revision of 

 the atomic weight of praseodymium which yielded 

 the number Pr - 140-94 with a material separated 

 from cerium and lanthanum for the first time by 

 direct methods (not fractionation). The value ob- 

 tained agrees exceedingly well with that obtained by 

 Baxter and Stewart in 1915, who found Pr= 140-924, 

 but were unable to remove cerium and lanthanum 

 entirely. 



A revision of the atomic weight of tin carried out 

 by Brauner and Kf epelka, and later on by Kf epelka 

 alone, gave the value Sn =118-699, agreeing exactly 

 with that obtained by other authors. In conjunc- 

 tion with Th. W. Richards, Kfepelka determined the 

 atomic weight of Al =26-963 based on the analysis 

 of the bromide, AlBr^ ; this revision carried out at 

 Harvard University is being continued in Prague 

 on the chloride, AICI3. 



Scandium was prepared by Prof. Sterba-Bohm 

 in a state of " spectral " purity (Honigschmid found 

 with this material Sc =45-10). 



The close analogy between boric and aluminic acid 

 has been shown by Dr. J, Heyrovsky, who made a 

 physico-chemical examination of solutions obtained by 

 dissolving (amalgamated) aluminium in aqueous solu- 

 tions of the hydroxides of the alkalies, alkaline earths, 

 and of ammonium. He ascertained that the process 

 in all cases is additive, consisting in the formation 

 of a complex anion Al(OH)4^, provided that the cation 

 is strongly positive. He also determined the basicity 

 and acidity of aluminium hydroxide and its bearing 

 on the electrolytic potential of aluminium. Alu- 

 minium must be regarded as the true " Ekaboron " ; 

 in the constitution of the above compounds, ap- 

 parently pentavalent, it is really positively trivalent 

 aluminium (4 + and i - =3 +), as was explained by 

 Brauner in his preface to a text-book of analytical 

 chemistry. 



Organic Chemistry. — Prof. Voto6ek, of the 

 Bohemian Polytechnic High School, is continuing 

 his well-known work on sugars and has analysed 

 with Burda the sugar components of lichens.] 



Analytical Chemistry. — Prof. Sterba-Bohm and 

 Vostrebal worked out an exact method for the 

 quantitative determination of molybdenum as tri- 

 sulphide, using an admixture of formic acid on account 

 of its high dielectric constant. 



For the analysis of minerals the result of StSrba- 

 Bohm and Rosick^'s investigation of the new mineral 

 " ultrabasite," from Freiburg in Saxony, is important ; 

 " basic " sulphides of silver and lead preponderate 

 over the " acid " sulphides of tin and germanium. 

 It contains 2-2 per cent, of germanium; thus ultra- 

 basite becomes the fourth known germanium-con- 

 taining mineral. 



Zoology. — Our most prominent investigator in 

 this branch of science is Prof. Frantisek Vejdovskjf, 

 of the Bohemian University, who finished during the 

 war his life-work, " The Structure and Development 

 of the Living Substance " (in English). This work 

 contains many coloured drawings (illustrations), but 

 owing to the want of the necessary means the author 

 was hitherto unable to publish it. 



Vejdovsk;^'s successor. Prof. Mrdzek, is very active 

 in the zoological investigation of Bohemia with 



NO. 2741, VOL. 109] 



special regard to the ecology of the lower animals in 

 ponds and lakes. 



Systematic Botany. — Prof. Josef Velenovsky, the 

 chief of our school of systematic botany, who is well 

 known for his leading work " Flora Bulgarica," has 

 just published another great work, " Bohemian 

 Mushrooms," 4 vols. 920 pp., Prague, 1920-1922, 

 which is richly illustrated. In order to study all 

 kinds of fungi growing in Bohemia, he lived for a 

 series of summers in the chief big forests of our 

 country. He finds, inter alia, that far more mush- 

 rooms are edible than is generally accepted, but there 

 are some which are poisonous or edible according to 

 the weather and season. From his institute a series 

 of papers was published by Domin, Kavina, Schuster, 

 Danek, containing interesting morphologic, cytologic, 

 etiologic, and phytogeographic studies. 



Prof. Domin, also of Bohemian University, continues 

 his plant geographical investigations, especially with 

 regard to Australian plants and also the Alpine flora 

 of the Tatra Mountains. 



Plant-physiology. — In this department excellent 

 modern work has been done by Prof. Bohumil 

 NSmec, who has published two recent text-books : 

 " Introduction into General Biology " and " Plant- 

 anatomy and Plant-physiology." He has also pub- 

 lished a series of papers on the Cecidia of the 

 Eriophylages, on the infection of root-tubercles of 

 Ornithopus, and on the influence of centrifugal force 

 on plant cells. It is known that he was the first 

 to explain geotropism. It should be mentioned that 

 from his school O. Vodrizka proved the presence 

 of a special statolithic starch in the blossoms and 

 sheaths of positively geotropic plants with nyclinastic 

 motions. J. Peklo isolated a symbiotic bacteria 

 (azobacter) from the mycetocytus of the plant-louse 

 Schizoneura lanigera. The work of VI. Ulehla on the 

 analysis of lateral and negative geotropism of 

 Pharbitis and its role in the climbing character, and 

 also that on heredity of A. Bro^ek, who succeeded 

 in obtaining a mosaic bastard from two pure lines 

 of Monulus, and studied the case of a simple 

 Mendelian heredity in blossom-patterns, should also 

 be mentioned. E. Senft has described the role of 

 slime-trichoms in germination. The object of other 

 work in this institute is the physico-chemical in- 

 vestigation of plant-life and also its connection with 

 the chemistry of colloids. 



Geology, Petrography, and Mineralogy. — 

 These three have the best traditions of all sciences 

 in Bohemia, for they were cultivated by the most 

 prominent men of science since about 1800. The 

 conditions of publication during the war and after 

 permit only of printing special papers of a very 

 limited extent in the Transactions of the Bohemian 

 Academy or of reviewing articles in journals with a 

 broader programme. 



Of the geological formations in the Bohemian 

 countries the best known are those which Barrande 

 united under the title " Systeme silurien," making 

 them classical territory in his gigantic palaeontological 

 work, " S. S. du Centre de la BohSme." To-day, 

 putting those formations together under the designa- 

 tion " Barrandien," on account of a tectonic common 

 to them, we distinguish them into a succession from 

 the Algonkian to the Devonian. 



The research of Barrandien hitherto done was 

 principally palaeontological ; for the solution of strati- 

 graphic and tectonic questions a petrographic 

 knowledge of eruptive and sedimentary rocks and 

 the conditions of their origin was wanting. During 

 the last few years this work has been organised and 

 carried out by Dr. FrantiSek Slavik, professor of 

 mineralogy and petrography in our University, with 



