I30 JAMAICA, 



iiience ; the air braces the tone of the fibres, renders the fpirits 

 lively, and creates an hnmoderate appetite for food, which unfor- 

 tunately is not here in fuch abundance as to be proportionate to the 

 demands for it. Hence it may be fuppofed, that frofts are frequent 

 en the Blue Mountain fummits during the winter months, as 

 fome have pofitively aiieited [w". Thofe fummits have been ex- 

 plored by very few perfons; the air at fuch a height is almofi too 

 pure for human refpiration. I have been informed that fome Ne- 

 groes died in paffing over them, iome yens ago, before the paci- 

 fication was made with the rebels in this ifl.md. Thefe fummits 

 are bare of trees and Ihrubs, but well covered with a thick mofs, 

 which gives harbour to vaft numbers of rats. In what manner 

 they procure lubfiilence in lb dreary a refidence, I have not been able 

 to learn. 



I mull not be filent on a phaniomenon, which I do not find no- 

 ticed by any writer of our natural hiftory. I fhould, however, 

 premife, that, in regard to the faft, it was communicated to me by 

 a gentleman of fuch ftri£t veracity, as not to admit a Ihadow of 

 doubt. He related it as a fingularity which he could not readily 

 account for, but had been obferved by many perfons living near the 

 Yallahs and ButF Bay rivers. During the months of November, 

 December, January, and February, when little or no rain falls, 

 feveral rivulets of water are obferved to gulh from the North fide 

 of the Ridges, which increaie and fwell the tide of thefe rivers 

 very confiderably : but they are not remarked at other times of the 

 year, even after the heaviell: rains. The prodigious mantle of thick 

 mofs which cloathes thefe Ridges, extending over many hundreds, 

 if not thoufands of acres, receives and imbibes the water that 

 almofl continually diftils upon it from the vapours that brood over 

 their fummits. Thefe rivulets are not leeii until after the perio- 

 dical North winds are fet in, which ufually happens in the be- 



[■ju] According to a very accurate trigonometrical ireiifaration, lately taken by Dr. Alexander 

 M'Kenzie, affilkd by Mr. George Gauld, fuvveyor to his inajelly, the refults were as follow : 



Feet Height. Mile. 

 Catharine Mill, "I above the r 5050 = 1 wanting 230 feet. 



Blue Mountain Summit, J fea's level, \ 7553 =. li ditto 367 ditto, 



eonfenuently, the mercury in the barometer (agreeably to Dr. Halley's calculatiotis) ought ta ftaad 

 oa the Blue Mountain at about 22 -j-'o?^ inches. 



ginning. 



