110 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



ing results consists in showing that the average quantity of 

 rain that fell by day is about three per cent, greater than the 

 quantity tliat fell by night; while, on the other hand, the 

 Qiumher of nights on wOiich rain fell was fifty per cent, great- 

 er than the number of days on which rain fell. In March 

 more rain falls in the night than in the day ; in August more 

 rain falls in the day than in the night. On considering the 

 geographical distribution of his stations, he shows that the 

 higher regions of the island receive more rain than the low- 

 er ones, in the proportion of sixty-five to forty-four inches ; 

 the former beinix the averasfe rain-fall of those stations that 

 are one hundred feet above the sea, while the latter figure 

 belono*s to the stations less than one hundred feet above the 

 sea. In reference to the distribution of the rain-fall with the 

 seasons, he arrives at the startling conclusion that from Feb- 

 ruary to May the rain-fiill in the first ten years was twelve 

 inches, that since that period it has steadily diminished, and 

 is now scarcely six inches. 



In studying the effect of the rain-fall upon the sugar crop, 

 Rawson makes a careful analysis of the systematic records 

 of the custom-house, which have been kept continuously 

 since 1806. After allowing for the influence of various po- 

 litical acts, such as the emancipation of 1838, Avhose influence 

 was felt in agricultural matters until the year 1847, and al- 

 lowing for tlie effect of the rapid increase in the use of guano 

 and other foreign fertilizers, wliich took place between the 

 years 1851 and 1857, he makes the following inferences: 



The I'ain-fall affects in most cases the crop of the follow- 

 ing year, but that of the current year only in a slight de- 

 gree. This results from the fact that the rain-fall of the first 

 six months is less than one third of the whole annual rain- 

 fall. The crop is off' the ground before the rains commence 

 which chiefly nourish the young sugar-cane. In almost ev- 

 ery case the excess or deficiency of the crop is accompanied 

 by a low rain-fall in the preceding year. The effect of a very 

 small rain-fall is more decided than the effect of a heavy rain- 

 fall. A dry season is likely to injure the crop by one fifth 

 more than a wet season is likely to benefit it. In examining 

 the influence of the rain-fall of each individual month upon 

 the crop of that year, Rawson finds that the chances are on 

 the average about three to one that a wet February, a dry 



