269 
her the advantage over England; but it is the superior 
skill, industry, and management of her farmers ; so that the 
grand defect in the present state of farming in England and 
Scotland, — that in which they are behind not only Belgium, 
but China, Switzerland, and some parts of Germany and 
France, is the rigid adherence, on all lands, to nearly the same 
system, the production of only one annual green crop, instead 
of two from the same land, and particularly allowing the 
turnip to consume a whole vegetating season in its growth, — 
too^ether with the total neo^lect and waste of the most valua- 
ble portions of the manures : and it is only by imitating the 
rural economy of these countries, by obtaining a quicker 
succession of green crops, by taking every opportunity to 
warmer than the mean of England. T'ne autumns are the same in both coun. 
tries. The climate cf Great Britain is, however, subject to considerable variation; 
there is frequently a difference of 4.8'' degrees in different years at the same 
locality, and as much as 10° in the same month in different years. The mean 
temperature of 4.8 is capable, when added or subtracted for the whole year, of 
producincT a decided difference in our seasons. But these variations of climate 
range through periodical times. Mr. Luke Howard, of Ackworth, says, " The 
extent of the periods, for v.ant of a sufficient number of years of accurate obser- 
vations, cannot at present be fully determined, but they have the appearance of 
being completed in seventeen years." In a paper about to be published in the 
Transactions of the Royal Society, Mr. Howard proves that " these cycles of tem- 
perature correspond with 223 sy nodical revolutions of the moon, or the return of 
this satellite to her nodes; i.e., a period of eighteen years: that there are nine 
years in which there is, with some fluctuation, a mean descending temperature, 
and nine of ascending temperatures ; the years of low temperature being wet and 
unfruitful, and those of ascending, the contrary. That the present year of 1841 
is the turning year from the cold to the warm series of years." 
If this view of the seasons be correct, the northern portion of England will 
enjoy, during the nine warm years, a climate superior to that which the south of 
England had during the nine cold years ; for the annual mean temperature of the 
extreme north of England (Carlisle) is 48°, while that of the extreme south 
(Sandwich) is 50° ; and therefore there is a full answer to all objections respect- 
ing the double cropping performed in the south, which is said not to be capable of 
being effected in the midland and northern counties, because the climate of the 
south is so much superior ; except it could be proved that these double crops are 
only obtained in the south during the nine years of ascending or warm tempera- 
tures, which it is impossible to prove. So that during nine years out of eighteen, 
the northern and midland parts possess the same, if not a superior climate, than 
the southern possessed during the preceding nine cold years. 
The years of productiveness, as shown by the price of corn, seem to run in 
cycles of eight years of descending, and six years of ascending temperatures. 
