"^ 
354 
BOTANY OF THE YOYAGE OF H.M.S. HERALD. 
crystals ; and quartz traversing tlic latcrite in djkes of variable thickness. Masses of trap 
are also met with, translucent crystals of carbonate of lime not unfrequently found in the 
centre of the blocks of syenite, and the beds of ravines afford fragments of laminated mica. 
No signs of stratification or of volcanic action are discoverable. At the base of the primary 
ridge, in those places where it terminates at some distance from water-mark, and between 
the various spurs, patches of alluvial soil are found, consisting exclusively of decomposed 
vegetable matter washed down by the rains, and mingled with the laterite. These are 
sedulously turned to account by the natives for agricultural purposes, and, owing to care in 
manunng and irrigation, are sufficiently productive. The numerous ravines by which the 
flanks of the hills are cleft, furnish a never-faihng supply of water, remarkable for its extreme 
pnnty ; and a little below one of the loftiest peaks a considerable spring arises, the singular 
position of which leads to the belief that it may have a submarine communication with the 
mainland. Diu-mg the summer season these streams become greatly swollen ; and the spec- 
tator sees the angles of junction of the spurs and main range distinctly traced out, by lines 
of foam mdicatmg the course of these turbulent cascades. 
The chmate is subject to a variation of temperature, from 47° to 93° Fahr The daily 
range rarely exceeds 15° Once only, during the years 1844-1851, did the thermometer 
sink as low as freezing-point.* Towards the end of October or the commencement of No- 
vember the north-east monsoon sets in. The atmosphere is now wonderfully serene ; the 
air cold, bracing, and dry; and the transition from an atmosphere saturated with moisture is 
marked by the warpmg and splitting of tables and other wooden articles of furniture ac- 
compamed by considerable noise, and the curiing up of papers, as occurs in" this climate 
iddl T T^ ^ i" " '"^ '■°°""- '^^ " '^'' ""^''^^■' "l^'^h endures until about the 
middle of February, during which scarcely any rain falls, and vegetation is dried up and 
scan y, a few Co,„pos./a^ being neariy aU that can be found flowering. Gradually the tem- 
pera m-e becomes higher, the atmospheric deposits greater, the dry, dLloured leaves of I 
Myule, .miasto..a, .nA EnMca fall, their branches kindle with a tender vernal green and 
nnumcrab e flowers spring up from the turf, until about May summer is herakfed t the 
advent of the south-west monsoon. This season is characterized by a most i tense and 
oppressive heat, which causes the greatest languor to European resiLts ; i: S foT^ 
January . 
February- 
March . 
April . . 
May . . 
June . . 
Max. 
73° F. 
78 
80 
87 
88 
92-5 
Min. 
49° P. 
50 
49 
49 
68 
75 
Mean. 
61-65° P, 
63-5 
65-7 
72-7 
78-3 
83 
July . . 
August . 
September 
October . 
November 
December 
Max. 
92° r. 
92 
93 
90 
85 
77 
Min. 
80° F. 
78 
78 
67 
57^ 
47 
Mean. 
85° r. 
83-5 
82-9 
80-3 
72 
63-6 
