234 



NATURE 



[November 22, 1917 



solution of the problem of smoke pollution. Yet this 

 problem in industrial and sanitary reconstruction will 

 nave to be faced when peace comes, iind for that reason 

 it st'ems unfortunate that the Local Government Board 

 Committee on Smoke Abatement should have inde- 

 finitely postponed its meetings on the outbreak of war, 



J. B. C. 



METEOROLOGICAL PERSISTENCE. 



THERE is a special sense of appropriateness about 

 the brochure entitled •" Konstant auftretende 

 secundiire .Maxima und Minima im dem Jahrlichen 

 Verlauf der meteorologischen Erscheinungen," by Dr. 

 Eli Van Rijckevorsel, published as No. 102 of the 

 " Mededeelingen en Verhandelingen " of the Royal 

 Meteorological Institute of the Netherlands. For the 

 last dozen vears the author has appeared to confine his 

 published scientific activity to the subject of the per- 

 sistence of secondary maxima and minima in annual 

 meteorological phenomena, and this is his eleventh 

 contribution on the same thesis, the last three of which 

 have received the support of his national institute. 



A detailed comparison of the whole series of " tracts " 

 would be necessary to enable us to dogmatise as to 

 the validity of the "author's conclusions and the justi- 

 fication of his persistence. There is no doubt, however, 

 that even this eleventh article taken by itself is full 

 of interesting points. A long series _ of_ seventy-two 

 years' barometric data from Christiania is dealt with 

 in two thirty-six-year portions, and also as to twenty- 

 five years allocated to sun-spot maxima and twenty- 

 five vears to minima in the same period. From the 

 sun-spot point of view, a similar process is applied 

 to shorter periods from Nertchinsk and Innsbruck. 

 The main part of the data, however, consists of daily 

 sums from thirty-three stations in the N. Hemisphere 

 for periods ranging from forty-three years at Hapa- 

 randa to faur at Honolulu and St. Vincent (Cape 

 Verde). The stations are well distributed, five with a 

 mean latitude of 67° and a range in longitude of 

 nearlv 100° ; eight with mean latitude 52°, and with 

 gaps in longitude of 120° for the Pacific and 90° for 

 the Atlantic ; nine with mean latitude 42°, and again 

 a gap of 120° in longitude for the Pacific; and eleven 

 with mean latitude 21" in which the Pacific gap is 

 partly bridged by Honolulu. Some of the tables ap- 

 pear to have had a decimal point omitted throughout, 

 and the Honolulu table differs considerably from the 

 others, but the principle of printing sums instead of 

 means, when the periods vary considerably, seems to 

 demand more explanation than the author has given, 

 though this practice has probably been adopted and 

 discussed in one of the ten earlier contributions which 

 are not for the moment at hand. 



An excellent series of plates shows the author's idea 

 of the variation with latitude and longitude of the 

 secondary oscillations with which he is dealing, and 

 there is also a comparison of the resulting oscillations 

 from a fifty winters' comparison of Greenwich baro- 

 meter and thermometer, showing a mean lag of half 

 a week from the barometric maximum to the tempera- 

 ture minimum ; a similar comparison in diagrammatic 

 form is given for Bucharest from a fifteen-year period. 



Altogether there would appear to be thirty-five 

 oscillations in the year superposed on the ordinary 

 single solar oscillation, but having regard to the classic 

 case of the three "icemen," now so generally dis- 

 credited in this country, it mav be some time before 

 Dr. Rijckevorsel obtains much enthusiastic support 

 among us, for though the realitv of the alternations 

 of weather is undeniable, our proverbial traditions 

 nearly all postulate, not the same, but different con- 

 ditions on a fixed date. W. W. B. 



NO. 2508, VOL. 100] 



THE SHORTAGE OF THE SUPPLY OF 

 NON-PHOSPHORIC IRON ORE.^ 



ALRE.\D\' in the pre-war years the supplies of 

 high-class haematite to the iron-smelting district? 

 of Europe trom the nearer sources wer^ getting short, 

 and tne lime was in sigtit when, tor iron ores iow 

 in phosphorus such as are required tor the 

 production of the " haematite grade" ot pig- 

 iron demanded by those who make sieel by 

 the '"acid" process, we shall have either to 

 turn our attention to sources of supply which are less 

 readily accessible, or so to improve metallurgical pro- 

 cesses' that, from ores which are abundant in closer 

 proximity to the coalhelds, trustworthy substitutes for 

 ■•Bessemer-grade" ami steels can be economically pro- 

 duced. The thesis advanced by the author of these 

 Howard lectures is that, notwithstanding that the 

 low-grade phosphoric ores of the Englisn Jurassic 

 rocks yield a pig-iron which for steel-making requires 

 refining upon a basic hearth, in Britain the second 

 of the two alternatives mentioned should be chosen. 



The subject-matter dealt with in the lectures was 

 assembled under two heads. In the first of the lec- 

 tures the author presented a conspectus of the various 

 ironfields where ore production is in progress within 

 the British Isles. In the second he passed in review 

 the various orefields in foreign countries w'hich, under 

 peace conditions, sent produce, either raw or semi- 

 manufactured, from their iron mines to supply the 

 British market. 



.Within the British area there is a remarkable 

 absence of any considerable concentration of iron ore 

 among geological formations of pre-Carboniferous age. 

 The non-phosphofic haematites of the Carboniferous 

 Limestone district occur as veins and impregnations, 

 and extend some little distance downwards among 

 these older rocks, but in their distribution they are 

 limited to a narrow belt of country which ranges 

 north and south through the English Lake District and 

 the Forest of Dean, and are probably of post-Carbon- 

 iferous date. They are less regular in their distribu. 

 tion, and therefore more expensive to exploit, than are 

 the bedded ores associated with the Coal Measures 

 or interstratified in thicker masses among the Jurassic 

 rocks, and the shortage of home supplies of haematite 

 has already long been felt. 



In former days clay-band and black-band ores, 

 interstratified anions' the Coal Measures, afforded the 

 main supply of English and Scottish iron, but when 

 steel superseded wrought-iron as the ordinary material 

 for constructional engineering, economic conditions 

 brought about the diminution of iron production from 

 these ores, and though there lie in reserve more than 

 thirty thousand million tons of such ore among our 

 Coal Measures, that source of supply does not at pre- 

 sent represent to our ironmasters a national asset 

 which has any great marketable value. 



Along the outcrop of the English Jurassic rocks be- 

 tween the coast of Dorset and the Cleveland Hills 

 there is nowhere any lack of low-grade iron ore. In 

 the neighbourhood of the Humber it is the Lower Lias 

 which carries the ore-bed, but generally the Middle 

 Lias is the more prolific horizon. In Northampton- 

 shire the great develooment of iron ore is in the basal 

 member of the Inferior Oolite series, and at Westbury, 

 in Wiltshire, and throughout the southern counties, the 

 most important development is in association with 

 Corallian rocks. "Just as the Carboniferous is the 

 great repository of Great Britain's fuel wealth, so the. 

 Jurassic is the bank which holds our fluid reserves of 

 iron ore. The gilt-edged securities of Cumbrian 

 haematite are sound, but not unlimited in amount; 



1 Abstract of the Howard Lectures delivered before the Royal Society of 

 Arts on April 30 and May 7 hy Prof. W. G. Fearnsides, Sorby Professor of 

 Geology in the University of Sheffield. 



