It is probable that some local
circumstances, perhaps the nature of the soil and the winds that
prevail in the flowering season, are the cause of this phenomenon.
In other regions, in the neighbourhood of Naples, for instance, the
coffee-tree thrives abundantly, though the mean temperature
scarcely rises above 18 centigrade degrees.
No person has ascertained in the island of Teneriffe, 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 colonies and meteorology,
and fully as important as the measure of the limit of the perpetual
snows. My observations furnished me with the data, set down in the
following table: -
Column 1: North latitude.
Column 2: Lowest height in toises at which snow falls.
Column 3: Lowest height in metres at which snow falls.
Column 4: Inferior limit in toises of the perpetual snows.
Column 5: Inferior limit in metres of the perpetual snows.
Column 6: Difference in toises of columns 4 and 5.
Column 7: Difference in metres of columns 4 and 5.
Column 8: Mean temperature degrees centigrade.
Column 9:
