20 THE METEOROLOGY OF JAMAICA 



in no way sheltered by trees or buildings. If the rain-gauges 

 cannot be placed so near the ground with safety, as is often 

 the case on sugar estates, they may be placed on the top of 

 a post 5 feet high, firmly planted in any open ground. The 

 height of the receiving surface above the ground, as well as 

 the elevation of the place above the level of the sea, should 

 always be stated in the register. 



In Jamaica the hundredths of an inch are often called 

 "parts"; thus a rainfall of 2*03 inches, or two inches no 

 tenths and three hundredths, is often written 2 inches and 

 3 parts. It would often save confusion to adhere to the 

 proper decimal notation. When no rain falls 000 should 

 be entered in the register, and blanks should be left for 

 omissions to register. 



The rain-gauge should be registered daily at 7 a.m., 

 before the sun gets hot, otherwise there will be loss from 

 evaporation. But the rainfall should be entered in the 

 register for the preceding day, and not for the day on which 

 the entry was made. The necessity of this is obvious, as the 

 rains generally fall after noon. 



There are about 200 rain-gauges registered in Jamaica, 

 but they are very irregularly distributed ; and in consequence 

 of this irregularity, the island was divided into four divisions. 

 Now if the average rainfall be obtained for each division, the 

 average rainfall for the whole island may be obtained by 

 adding together the average for each division and by dividing 

 by 4, no matter how many gauges may be registered in one 

 division and how many in another. 



The northern division comprises the northern shores from 

 Port Maria to Davis' Cove, including the central part of the 

 island, which forms the central sub-division; the southern 

 division comprises the southern shores from Holland Bay to 

 South Negril ; the north-eastern and west-central divisions 

 are the remaining parts of the island, bounded by the sea and 

 the other divisions. Their relative areas are as follows : 



North-eastern division ... ... ... ... ... 25 



Northern and central ... ... ... ... ... 22 



West-central 2(> 



Southern 27 



100 



