1841.] On Porcelain Clay found at Mangalore, 6jc. 969 



but its annual range of temperature is very small, and it may be said, 

 that the season of spring reigns throughout the year ; yet, though there 

 be no winter, the heat is never sufficiently great to bring the more 

 delicate Europe fruits to perfection, and at this height we can only 

 expect the successful cultivation of corn and of vegetables. The 

 valleys, which have a height of from five to six thousand feet, enjoy 

 the climate of Italy, the climate of the vine, the olive, the orange, 

 and the mulberry. The tea tree is cultivated in China between the 

 latitudes of 27° and 31° in a hilly country, and consequently in a 

 climate probably of 70° to 73° of mean temperature. Such is nearly 

 the mean temperature of the valleys in the neighbourhood of Kota- 

 gherry, and of many others along the Eastern and Northern faces 

 of the hills. The cultivation of this valuable plant might therefore be 

 attempted here, and with a much better chance of success, than 

 in almost any country beyond the limits of China. A little lower 

 down than this, coffee might be produced ; its native habitation being 

 on the sides of the lofty mountains of Yemen, and nearly in the same 

 latitude as the Neilgherries. 



But with all these advantages of climate, there are certain peculia- 

 rities, which in some situations prove most injurious to vegetation, and 

 if overlooked in any schemes for the improvement of agriculture or 

 horticulture in these regions, might mar our best exertions. These 

 are; 1st, the great intensity of the solar rays when the sky is not ob- 

 scured by clouds ; 2d, the great waste of heat from the ground and 

 from plants by radiation in clear nights. The former will sometimes 

 produce a heat of from 90° to 100° on the surface of leaves, flowers, 

 and fruit during the day ; the latter may subject them, in the suc- 

 ceeding night, to a degree of cold considerably below the freezing 

 point. Few plants will bear so great a transition, and it is only to be 

 avoided by a judicious selection of situations, which are not likely to 

 be much under the influence of the two causes I have noticed ; or 

 in the case of fruit trees, and garden plants, by matting and other 

 contrivances. I need scarcely remark, that it would be highly desir- 

 able to ascertain the meteorological characters of the different parts 

 of the hills, before attempting the introduction of any new staples ; 

 otherwise, in a new country, and without experience, success would 

 be very questionable, and would rest only upon blind chance. 



