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XIII. Notices respecting New Books. 



A Cycle of Eighteen Years in the Seasons of Britain ; deduced from 

 Meteorological Observations made at Ackworth in the West Riding 

 of Yorkshire, from 1824 to 1841; compared with others before 

 made for a like period {ending with 1823) in the vicinity of London. 

 By Luke Howard, Esq., F.R.S. With Five Plates. London, 

 Leeds, and Pontefract, 1842, pp. 22, 8vo. 



WE are happy to find from the little work now before us, that this 

 veteran meteorologist is still prosecuting his labours with his 

 pristine ardour ; and we congratulate him on the result, now, as he 

 truly states, ascertained beyond controversy, that a periodical revo- 

 lution takes place, bringing alternate warmth and coldness through 

 successive trains of seasons in our variable climate. We do this 

 with the greater satisfaction, because we think that between the 

 torrents of shameless empiricism on the subject of predicting the 

 changes of the weather, on the one hand, and the profound and ex- 

 tensive systems of meteorological observations on the other, which 

 have been brought forward and pursued within the last few years, 

 Mr. Howard's researches, more humble perhaps than the latter, — yet 

 admirably adapted for mathematical investigation, — and which ought 

 to have been a sufficient antidote to the former, have been in great 

 measure forgotten, and when not forgotten still not duly regarded. 



In his account of the climate of London, first printed 1818-1820, 

 and reproduced with many additions and improvements in 1833, Mr. 

 Howard gave a view of the series of changes embraced by the cycle 

 which it is his present object to illustrate, on the basis which his 

 observations then seemed to present, of alternate periods of seven 

 and ten years, the former ascending, the latter descending in the scale 

 of heat. He then admitted, from appearances, the probability of 

 spaces between these successive periods not agreeing with this rule, 

 and answering to the " intercalations " of an imperfect calendar. 

 Having since pursued the subject further, he finds " these spaces or 

 interposed years to be necessary parts of the scheme at large, which 

 now resolves itself into a cycle of eighteen years, in which our sea- 

 sons appear to pass through their extreme changes in respect of 

 warmth and cold, of wet and dryness." 



In the Proceedings of the Royal Society for March 1 1 and April 

 29, 1841 (or Phil. Mag., Third Series, vol. xviii. p. 552-559), are 

 given abstracts of papers containing the author's views on this sub- 

 ject, as regards the seasons near London, then read before the So- 

 ciety ; and one of those papers, relating to the periodical variations 

 of the barometer from year to year in this neighbourhood, has since 

 been published in the Philosophical Transactions*. 



* In the paper last mentioned, " On a Cycle of Eighteen Years in the 

 Mean Annual Height of the Barometer in the Climate of London, and on 

 a constant Variation of the Barometrical mean according to the Moon's 

 Declination," the author showed that the barometrical mean in this cli- 

 mate is depressed (on an average of years) by the moon's position in south 



