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[Page 2]
sunshine, where the plant is placed, & I will venture to say the difference of temperature indicated will be not less than fifty degrees. It is true the evaporation from the leaves of the plants would prevent their becoming as hot as the thermometer, but never the less, I have found the leaves of evergreen trees in this climate to grow very hot in warm & bright days, & the leaves of plants & the whole of their fluids must become very highly heated by the force of a tropical sun. The following experiment will also, shew that a thermometer placed in the shade of a House, or other broad object, does not, by any means, truly indicate the heat of the air in which plants in the vicinity are growing. I placed one thermometer within the shade of my house in July last, & another which I effectually skreend from the sun by only a covering of several fold of paper; but the sun shone brightly upon the plants & soil continuous, where the thermometer in the situation last described indicated a temperature of ten degrees higher than the other, owing to the heat what was reflected from the contiguous ground & plants; though there was at the time a considerable current of air. If this experiment were had been repeated at Madrass, & the body of the thermometer wholly shaded, I suspect that a difference of not less than