May 12, 1898] 



NATURE 



31 



For this purpose I will here employ a simple meteorological 

 method, which seems to have been little used among us hitherto, 

 viz. algebraic addition, step by step, of a series of plus and 

 minus values ; the resulting figures being then plotted as a curve. 



Suppose e.g. any set of such values, as follows : 



+ 3 + 6 - 2 + 8 + 12 - 3 - 9, &c. 



By addition we get this series : 



+ 9 + 7+15 + 27 + 24+15, &c. 



This latter series is thrown into a curve. 

 In his British Rainfall for 1881, 1891, &c., Mr. Symons has 

 given a series of rainfall values for a number of stations in 



/g3o 'T 'UC 'S~ '&0 '5' <io 'S" *70 'S' 'Po 'S "90 '^ 



t^lO~'i' 'UO y '.S-Q 'S '60 S 70 'y '9a '5- '<?a 'if 

 A, Boston ; b, Oxford ; c, Chilgrove ; d, Exeter ; e, Kendal ; f, Bolton. 



different parts of England (from 1830 onwards) ; also the per- 

 centage equivalents of these, the average for each station being 

 taken as 100. These latter I have made use of, taking the 

 excess over 100 as a plus value, and the deficiency under 100 as 

 a minus. Thus e.g. 106 would be + 6 ; 94 would be - 6. 



When this has been done with the values for Boston, in Lin- 

 colnshire, and the series treated by the addition-method de- 

 scribed, we get the curve marked A in the diagram ; and it is to 

 this curve I would especially invite attention. For it is to the 

 eastern parts of our country that Bruckner's cycle applies ; the 

 west belongs to what he calls Ausnahmegebiete, or exceptional 

 regions. 



Bearing in mind that these curves rise for plus values and fall 



NO. 1489, VOL. 58] 



for minus, we note in this Boston curve a general rise from 1838 

 to 1849 (or 1852), also from 1874 to 1883 ; while we have 

 general fall from 1852 to 1874, and from 1883 to 1896 (the last 

 point dealt with). In other words, the two former were wei 

 periods, the two latter dry periods. 

 The following figures show this : 



Between the wave crests 1849 and 1883 are 34 years ; and 

 between the wave hollows 1838 and 1874 are 36 years. Or, if 

 we like to take as approximate centres of the wet periods (say) 

 1843 ^"^ 1878, we have about the same interval, 35 years. 



These fluctuations, standing alone, would clearly be too slender 

 evidence of a cycle. But Bruckner claims that his cycle of 35 

 years has been in evidence in various parts of the globe through 

 these two centuries at least (since 1700).^ If the eastern part of 

 England, then, may be expected to conform to the law in 

 future, we might reasonably, perhaps, look for the centre of 

 another wet period somewhere in the second decade of next cen- 

 tury. And for the near future (without attempting detail) a 

 continuation for some years of the recent regime seems not un- 

 likely, dry years preponderating over wet. That is, the curve 

 should go down further, on the whole, for some years yet. 



I have given a number of other curves for comparison, viz. B, 

 Oxford ; c, Chilgrove, in Sussex (near Chichester) ; D, Exeter, 

 less reliable perhaps (see Brit. Rf., 1881) ; E, Kendal ; and F, 

 Bolton, in Lancashire. As we go westwards, the curve seems to 

 degrade somewhat (regarded from our standpoint), though the 

 same type may be di.scerned. In the northern curves, Kendal 

 and Bolton, we find little in common with the Boston curve, 

 though something like a 35 years' interval may, in cases, be 

 made out. 



It may be well to state that other stations in the east of 

 England yield very similar curves to that for Boston. 



^ ^ ^ A. B. M. 



Prehistoric Egypt. 



I NOTICE a review in Nature containing some statements 

 about my own work which are inaccurate. 



The term " New Race" is quite correct, as the race was en- 

 tirely new to us, whatever their age ; and as a tentative name 

 which commits us to no theories, it can hardly be said that I 

 "did not understand the facts of the case" in using it. In 

 dating the race to at least 3000 B.C., I was doing all that the facts 

 warranted at the time ; and if we all agree now that they are 

 older, it is by mere consensus of guessing, for no absolute proof 

 of earlier age by juxtaposition with other things has even yet 

 been found. 



Further, Dr. Verneau's erroneous assumption that the con- 

 dition of the bones could be produced by exposure to the air 

 alone, is quoted, with the remark that my "sensational discovery 

 therefore falls to the ground." How exposure to the air can 

 possibly break off the ends of bones and scoop out the cellular 

 structure, while the bone remains hard and firm, not even Dr. Ver- 

 neau can explain. To deny cannibalism in such a case, reminds 

 one of the indignant repudiation of the intention to smoke by a 

 man who already has a pipe in his mouth and a match in his 

 fingers. 



No one values more than I do the discoveries of M. 

 de Morgan ; but had he dealt more with strict evidence and full 

 details, and given weight to many facts which he has ignored, I 

 venture to think that his work would have needed less revision 

 in future. W. M. Flinders Petrie. 



University College, W.C. 



I HAVE read Mr. Petrie's letter, and I still think that M. 

 de Morgan is right, and that Mr. Petrie is wrong. I also think 

 that Dr. Verneau is right, and that his "assumption" is not 

 "erroneous." Mr. Petrie's reference to the revision which he 

 thinks M, de Morgan's work will need is remarkable ; for his 

 own will — in my opinion — need much more ! however much 

 M. de Morgan's may need ! The Revip:\ver. 



1 We may here recall th.-it Bacon seems to have been aware of such a 

 cycle. 



