May 13, 1922] 



NA TURE 



627 



his collaborators, for the lower horizons from the 

 Algonkian to the Ordovician in their whole extent. 

 Slavjk and Prof. Kettner completed in a series of 

 publications the older research of Slavik on the 

 Algonkian ; Kettner worked up^in monographs the 

 lowest Cambrian (layers of Zitec) and the lower 

 siluric horizon of KruSnd Hora from the point of 

 view of the genesis of the sediments ; Dr. Slavik, 

 with Mrs. Dr. Slavik, has described the oolitic 

 chamoisite ores, their sedimentary genesis and 

 the circulation of phosphorus. 



Numerous other papers on the Barrandien by 

 Kettner, Kodym, Purkyn?, now director of our 

 State Geological Institute, and Prof. Woldfich, give 

 detailed tectonic pictures of the single districts ; 

 Kettner and Kodym have proposed a change of 

 Barrande's designation of the horizons which is in 

 agreement with the recent results of their in- 

 vestigation. 



Another formation which is extended over large 

 areas in Bohemia and Moravia and richly divided is 

 the Cretaceous formation. The detailed stratigraphy 

 and facial change of this formation has been for 

 more than thirty years the object of thorough 

 studies by Cenek Zahalka, who has published great 

 monographs of the Cretaceous formation in Pod- 

 fipsko, Stredohofi and Eastern Bohemia, whereas 

 the environments of Prague were in this direction 

 investigated by his son, Bretislav Zahdlka ; special 

 studies were made by Woldfich. 



As regards the petrography and geology of plutonic 

 eruptive rocks and crystalline schists, two territories 

 were intensively studied within recent times : the 

 Bohemian Forest and the granitic massive of Middle 

 Bohemia. 



The work of Sokol on the Bohemian Forest has 

 yielded a basis for broader studies of the primary 

 inhomogeneity of the magma. 



The ore deposits were also intensely investigated, 

 especially the gold-veins and beds of iron ores (Mrs. 

 Dr. and Prof. Slavik, Kettner, Stoces). 



In special mineralogy a series of crystallographic 

 papers was published (Jeiek on Johannite, Ondrej on 

 the Bohemian quartzes, Rosicky on the topaz and 

 gypsum, ^ Slavik on the lacroisite), and chemical 

 papers (Splichal on the products of decomposition 

 of the felspars, Rosicky and §terba-B6hm on the 

 ultrabasite) . 



Geography. — During the war this science centred 

 round the " Bohemian Geographical Society," which, 

 in spite of the difficult conditions, was able to issue 

 its transactions in the " Sbornik." Owing to the 

 Austrian censorship political geography was very 

 limited and chiefly physical geography was cultivated. 

 The fall of Austria means, of course, a new era for 

 our political geography. Prof. DaneS's studies on the 

 population of the industrial districts of Bohemia and 

 Prof. Dvorsky's on Yugoslavia as well as his book, 

 with a political programme, on the territory of the 

 Czechoslovak people, are the prominent works in this 

 branch. A great work was started in ethnography 

 with the lirst volume of the " Ethnography of the 

 Czechoslovak People " (editor K. Chotek). 



The chief geomorphological works based on geology 

 and tectonics are : Prof. DaneS's on the " Kras " 

 (Kars) of Australia and Java, Absolon's on the 

 Moravian " Kras " (Kars), Dedina's on north-eastern 

 and Sokol's on western Bohemia, and Vitdsek's 

 on the upper Odra district. An interesting mono- 

 graph on Czechoslovak earthquakes has been written 

 by Kolacek. The military geographical State Insti- 

 tute, founded at the beginning of the Republic, 

 published a series of fine maps of our new state, both 

 charts of large areas as well as special maps, i : 25,000 

 and I : 75,000. 



Wheat Prices and Rainfall in Western Europe. 



TN an article on " Weather and Harvest Cycles " | 

 ^ in the Economic Journal of December last Sir 

 William Beveridge gave index-numbers showing the 

 tiuctuation of wheat prices in each year from 1500 to 

 1869, and made a preliminary mathematical and 

 arithmetical analysis of these figures with a view of 

 discovering periodicity in the yield of harvests, 

 which might be attributed to periodicity in the 

 weather. In a paper read to the Royal Statistical 

 Society on April 25, he has now given the results of 

 a much fuller analysis, involving a test of the same 

 figures by harmonic analysis, for the discovery of 

 practically all possible periods between 2 and 84 

 years' length. The following is a summary of the 

 paper. 



The amplitudes for more than 300 trial periods 

 altogether have been calculated for a sequence of 

 about 300 years from 1545 onwards, while for a 

 number of these trial periods amplitudes have been 

 calculated separately for the first 150 years and for 

 the second 150 as well. These are shown on a 

 periodogram from ^=150 (2 years) to q — yb (84 

 years). Each of the apparent periods indicated by 

 the periodogram is considered in the light of four 

 tests of periodicity : namely, the test of intensity 

 (that is to say, comparison of the actual amplitude 

 with the expectancy) ; the test of changing signs 

 (both the elements a and h being required by theory 

 to change signs in the neighbourhood of a period) ; 



NO. 2741, VOL. 109] 



the test of continuity (that is to say, indicating the 

 same period, with agreement of phase as well as 

 length, in each half of the sequence) ; and the test 

 of agreement with other records (that is to say, the 

 discovery of a similar periodicity in rainfall, tempera- 

 ture, or some other meteorological element). Parti- 

 cular importance is attached to the third of these — 

 the test of continuity. 



The results of this analysis are summarised in a 

 table showing some 20 apparent periods ranging in 

 length from 2-2 to 68 years. These are arranged in 

 four groups : — 



(i) Periods the reality and persistence of which is 

 beyond doubt, strong evidence from the analysis of 

 wheat prices being confirmed by close agreement of 

 first-rate meteorological evidence. This group in- 

 cludes the period of 2-200 years discovered originally 

 by Mr. C. E. P. Brooks, and later by Mr. J. Baxendell 

 in rainfall ; the period of 5-1 years discovered by 

 Mr. J. Baxendell in wind and rainfall and by Capt. 

 D. Brunt in Greenwich temperature ; and the period 

 of about 35 years discovered in 1890 by Dr. Bruckner 

 in temperature, rainfall, and barometric pressure. 



(2) Periods strongly indicated by the wheat prices 

 but for which meteorological confirmation is, at 

 present, weaker or lacking. This group includes 

 seven periods of 5-671, 9-750, 12-840, 15-225, 19-900, 

 54-000 and 68-000 years. Most of these periods are 

 relatively long, a fact which helps in explaining failure 



