54 
TEMPERATURE OF LAGUNA. 
tliat the mean temperature of this town must be above 18'7° 
(15° It.), that is to say, higher than that of Naples. I do not 
lay this down as an unexceptional conclusion, for in winter the 
refrigeration of the clouds does not depend so much on the 
mean temperature of the whole year, as on the instantaneous 
diminution of heat to which a district is exposed by its local 
situation. The mean temperature of the capital of Mexico, 
for instance, is only 16'8° (13'5° R.), nevertheless, in the 
space of a hundred years snow has fallen only once, while 
in the south of Europe and in Africa it snows in places 
where the mean temperature is above 19 degrees. 
The vicinity of the sea renders the climate of Laguna 
more mild in winter than might , be expected, arising 
from its elevation above the level of the ocean. 1 was 
astonished to learn that M. Broussonnet had planted in 
the midst of this town, in the garden of the Marquis de 
Nava, the bread-fruit tree (Artocarpus incisa), and cinna- 
mon-tree (Laurus Cinnamomum). These valuable produc- 
tions of the South Sea and the East Indies are naturalized 
there as well as at Orotava. Docs not this fact prove 
that the bread-fruit might flourish in Calabria, Sicily, and 
Granada ? The culture of the coffee-trce has not equally 
succeeded at Laguna, though its fruit ripens at Teguesta, as 
well as between the port of Orotava and the village of St. 
Juan de la Rambla. It is probable that some local circum- 
stances, perhaps the nature of the soil aud tlio winds that 
prevail in the flowering season, are the cause of this pheno- 
menon. In other regions, in the neighbourhood of Naples, 
for instance, the coffee-tree thrives abundantly, though 
the mean temperature scarcely rises above IS centigrade 
degrees. 
No person has ascertained in the island of Tenerifte, the 
lowest height at which snow falls every year. This fact, 
though easy of verification by barometrical measurements, 
has hitherto been generally neglected under every zone. It 
is nevertheless highly interesting both to agriculture in the 
colonics and meteorology, and fully as important as the 
measure of the limit of the perpetual snows. My observa- 
tions furnished me with the data, set down in the follow- 
ing table: — 
