December 22, 1898J 



NA TURE 



175 



Where do we stand in Bruckner's Weather-cycle ? 



The problem of future weather is one which has a fascination 

 for many. Our present inability to get beyond (or much 

 beyond) the daily forecast, may well, at times, seem a reproach, 

 considering the immense amount of industry that has been given 

 to weather studies. Where is the professional meteorologist in 

 this country (we vainly ask), who, on the basis of some cycle, 

 or proved recurrence, or other facts, will tell us, even in the 

 most general way, what the coming years have in store for us? 



Vet the time may not be so very distant, I think, when science 

 will be able to say, Nous aiioiis chaj^s^c tout cela. The evidence 

 of cycles is growing ; and their character is being more exactly 

 fixed. An attentive reader of that excellent record, the 

 Meteot\ilogischt' Zeitschrift, may observe, now and again, a 

 feeler (so to speak) put forth into the obscure ; a serious attempt 

 to extend the range of prevision, a suggestion, by some well 

 equipped mind, as to the course of weather in coming years or 

 seasons. Have we not in such the hopeful beginnings (hopeful 

 even in case of failure) of a new and difficult art ? 



There are two weather-cycles, which have lately been (shall I 

 say ?) knocking for admittance ; that of I \ years, and that of 

 35 years. It is well to bear in mind thai these are not mutually 

 exclusive. They may be found to usefully supplement and help 

 each other. 



Bruckner's views as to the recurrence, at intervals of about 35 

 years, of cold and wet periods, alternating with warm and dry 

 ones, seem to have hardly received, as yet, in this country, the 

 attention which they deserve. They are destined, I believe, to 

 have a large influence on future thought about such matters. 

 It may be useful to ask how our London weather is related 

 to this 35 years' cycle ; and I propose to do so here from the 

 stand]ioint of barometric pressure. 



The method adopted is this : Each month, in a long series of 

 years (from 17S6), is first characterised as -f or - , according as 

 its pressure has been above or below the average. (Tables by 

 Eaton and Glaisher have been used for the purpose.) Then the 

 plus months in each year are counted, and the series of numbers 

 so obtained is smoothed by additions of \o{i.e. adding the first 

 10, then from the 2nd to the nth, the 3rd to the 12th, and 

 so on, each sum being put down in theyf/?/; place). This gives 

 us the dotted curve A in the diagram, in which may be seen, 

 underlying minor variations, a succession of long waves. 

 The general outline of these waves may be more clearly brought 

 out by a further smoothing process (continuous curve). ^ 



In order to clear understanding of this curve A, consider, for 

 a moment, its lowest point, that for 1842 ; this means, that, in 

 the 10 years, 1838-47, there were 50 months of + barometric 

 pressure, out of 120. Similarly, the highest point (that for 

 1891), means that in the 10 years 1S87-96, there were 67 months 

 of + pressure out of 1 20. 



Note the intervals between minima of this curve A. From 

 1813 to 1842, 29 years ; 1842 to 1876 (34 years). Or, taking 

 the twice-smouthed curve, we get 35 and 32 years. On the 

 other hand, the two completed waves are approximately bisected 

 by the vertical lines for 1830 and i860 (interval 30 years). 



At the top of the diagram are two linear series representing, 

 the one, Bruckner's warm and cold, the other, his dry and wet, 

 periods (warm and dry, continuous lines, cold and wet, dotted 

 lines). These two series, for temperature and rainfall, are not, 

 it will be seen, exactly coterminous ; the latter tend to lag some- 

 what on the former. Brlickner's general figures may be given, 

 so far as they here concern us.'-' 



Now, it will be noticed that our barometer curve \ at its 

 lowest points is generally about the middle of the cold periods, 

 while the middle of the waves is aliout the middle of the warm 

 periods. Also, that the parts of the twice-smoothed curve above 

 the average line are about coterminous with warm periods ; 

 while the parts below the average line are in general co- 

 terminous with cold periods. 



vth pl.-i 



NO. I 52 I, VOL. 59] 



It is surprising, I think, that an agreement so considerable 

 can be brought out by a method so rough 



Do not these facts throw some light on the future ? An 

 interval of 35 years from the last minimum, 1876, brings us to 

 191 1, about which time (perhaps a little earlier) we might fairly 

 look for another minimum, the middle of another cold and wet 

 period. At present we are still, apparently, in the warm and 

 dry period commencing about 1886, and probably near the end 

 of it, as (say) 15 years from 1885 brings us to the end of the 

 century. We next enter (by programme '.) on another time of 

 cold and wet, with preponderance of low barometers. Thus 

 our curve A should be turning down soon towards its next 

 minimum (situated somewhere between 1906 and 191 1). 



The rainfall aspect of the current warm and dry period may 

 be put thus : Of the fifteen years, 1883-97, twelve have been dry, 

 and only three wet. 1S82 seems to mark the end of 'a long 

 time of preponderance of wet years. 



The curve B is one for Paris, made out in the same way as A 

 (the data, however, extending only to 1893). I' shows much 

 the same kind of fluctuation. One curious feature is a lag in 

 the three minima behind those of the London curve. 



f7go s f3oo 'Sr '10 



VI -a •y-'f 'i'T' 'i''?o y v<7 'i- 



Regarding barometric pressure in these regions, Briickner 

 considers that in a dry period there is a deepening of the 

 usual cyclone in the North Atlantic (on an annual average), and 

 an intensifying of the ridge of high pressure reaching from the 

 Azores to the interior of Russia, especially in Central Europe ; 

 also a general increase of amplitude in the yearly variation 

 (Klimaschw., p. 2 1 7). In wet periods, the pressure differences 

 (both from place to place and from season to season) are 

 lessened. 



There can be little doubt that this cycle of Brlickner's 

 touches Ufe at many points, and that a promising field of study is 

 thus opened up. 'Take health for example. Briickner himself 

 shows how the mortality from typhus at Basle has varied 

 with the cycle (being worst in the dry periods). In a recent 

 valuable work on epidemic diphtheria. Dr. Newsholme correlates 

 the mortality from that disease in England with the thirty-five 

 years' cycle, showing that a succession of dry years aff^ord the 

 most favourable conditions for growth of the disease. 



Alex. B. MacDowall. 



Soakage into Glazed Porcelain. 



I MIX salt with water for occasional gargling, and keep it in 



a porcelain pot with a lid. Some weeks ago I began to use for 



the purpose a small well-glazed pot, in which cold cream had 



been bought a long time since. It was thoroughly washed by a 



