CINCHONA CULTIVATION IN JAMAICA. 
513 
•in their favour is, they thrive at comparatively low elevations (from 2500 to 3000 feet), 
and consequently sustain a warmer temperature for their development than the ordinary 
cmchongc. That they can produce quinine at a still inferior altitude is equally certain, 
for from a sample of few leaves forwarded from Mount Essex, at Bath, barely over 2000 
feet above the level of the sea, and at present constituting the temporary site where the 
majority of the Cinchona plants are placed, Dr. Daniell discovered they contained a 
tolerable amount of this and other alkaloids. Notwithstanding various local disadvan¬ 
tages of this position, it must be held in remembrance that during the greater portion of 
the year unceasing rains prevail, frequently in continuous torrents, when the atmosphere, 
saturated with humidity, copiously bathes, in the form of mists and dew, the tender 
leaves, and thus promotes their permanent vigour and maturity. 
In the recent experiments, the fact of the leaves having, according to a rough esti¬ 
mate, yielded so much as 075 to TOO per cent, of alkaloids, leads to the inference that 
the bark will supply a good average proportion of these febrifugal elements. In their 
extraction the formula followed was that directed by the Edinburgh College of Phy¬ 
sicians in the preparation of quinine from yellow bark, on account of the ease and sim¬ 
plicity of the process. The characteristic white acicular, or needle-like crystals of quinine 
deposited on the evaporating glass, could be plainly discerned by the naked eye, and 
presented a striking contrast to the larger, flat, four-faced oblique prisms of cinchonine 
procured from the residual liquor. From a few young leaves of the Cinchona micrantha 
and C. nitida, likewise gathered on the Cold-spring plantation, sulphate of cinchonine, 
with other amorphous crystalloids, probably cinchonidine or quinidine, were eliminated ; 
but, owing to the limited quantity of material submitted for analysis, no definite propor¬ 
tions could be ascertained. Nevertheless, it is a source of satisfaction to know that their 
constituent alkaloids have not been dissipated by removal to another country. Weddell 
had noticed that the C. micrantha often preferred the lower declivities of valleys and 
banks of rivers to other localities, but in regions invariably above 4000 feet elevation, 
and it is stated that the C. nitida chiefly flourishes in still more lofty altitudes. It 
would therefore be desirable that these species, if possible, should be introduced into 
a station situated on an adjacent mountain spur, and of corresponding height (the mess-house 
being 4050 feet above the sea), offers a fair criterion of the average local temperature of this 
zone. 
1859. 
Months. 
TEMPERATURE FOR YEAR. 
Rainfall 
in 
Inches. 
WINDS. 
Mean 
Minimum. 
Mean 
Maximum. 
Mean of 
Month. 
Mean monthly 
dew-point. 
January... 
GO-1 
69-4 
63-G 
67-8 
2-68 
N.W. Westerlv. 
February 
59-8 
08-3 
61-1 
57-9 
5-32 
S.E. N. Westerly. 
March ... 
50-9 
70-2 
64-1 
58-1 
0-G0 
N.W.and S. Easterly. 
April . 
61-1 
72-1 
65-9 
58-5 
G-75 
S.E. and N. Westerly. 
May . 
62-2 
72-4 
66-0 
60-6 
10 - 55 
N.W. Westerly. 
June . 
63-7 
G9-9 
66-4 
61-7 
12-48 
S.E. and N. Westerly 
July . 
G3-7 
74-2 
67-5 
GTS 
6-87 
N. Westerly. 
August ... 
64-5 
72-8 
67-7 
61-0 
4-38 
S.E. and JN. Westerly. 
September 
64-4 
73-5 
67-4 
61-3 
15"95 
N.W. Variable. 
October ... 
G4-7 
73-4 
67-5 
61-8 
10-97 
N.W. E.S.E. 
N ovember 
G3-6 
72-1 
6G’o 
G0'9 
9-20 
N.W. E.S.E. N.E. 
December 
61-8 
70-4 
65'2 
59-0 
2-10 
N.W. and E.S. 
The thermometrical observations made by Mr. Spruce, from June 19th to December 8,1860 
(the dry season), in the “red bark regions” of Ecuador, closely approximate to the preceding 
Table, as may thus be noticed:— 
Mean minimum 
Gl-5 
Mean maximum 
72-2 
Mean temperature at G r.M. 
67'8 
Highest temperature observed . 
80-5 
Lowest ditto .... 
57-0 
Entire range .... 
23-5 
Mean daily variation 
• 
• 
10-5 
