NINE P.M.
Exposed Th. On Earth On Grass
Temperature 61.2 64.3 55.8
Mean Diff. from Air 6.8 4.6 11.8
Max. Diff. from Air 10.5 8.5 17.0
Number of Observations 10 9 9
SOLAR RADIATION
MORNING Time Temp. Black Bulb Diff. Phot. 11.30 a.m. 85.5 129 44.5 … 10.30 a.m. 89.0 132 43.0 … Noon 90.0 132 42.0 10.140 Noon 85.0 130 45.0 … Noon 86.0 138 52.0 … Noon 90.0 138 48.0 … —————————————————————————— Mean 87.6 133 45.8 10.140
AFTERNOON Time Temp. Black Bulb Diff. Phot. 3 p.m. 85.5 116 30.5 … 3 p.m. 92.5 128 35.5 … 3 p.m. 92.0 120 28.0 … 3 p.m. 89.5 128 38.5 … 3 p.m. 93.5 144 50.5 … —————————————————————————— Mean 90.6 127 36.6 …
NOCTURNAL RADIATION FROM PLANTS
SUNRISE Mean
Air Temp. 61.0 57.0 57.0 58.5 57.0 50.0 50.5 56.0 55.9
Barley 56 46 52 52 52 45 43 … 49.4
Diff. 5.0 11.0 5.0 6.5 5.0 5.0 7.5 … 6.4
Calotropis 56.5 48.0 … … … 45.5 … … 50.0
Diff. 4.5 9.0 … … … 4.5 … … 6.0
Argemone 57.0 50.0 50.0 … … … … 49.0 51.5
Diff. 4.0 7.0 7.0 … … … … 7.0 6.2
NINE P.M. Mean
Air Temp. 68.5 70.0 69.0 74.0 62.5 67.5 61.0 … 67.5
Barley … … … … 51.5 67.5 50.0 … 56.3
Diff. … … … … 11.0 10.0 11.0 … 10.7
Calotropis … 65.0 57.0 59.0 … 62.5 … … 60.9
Diff. … 5.0 12.0 15.0 … 5.0 … … 9.3
Argemone 56.0 67.0 57.0 … … … … … 60.0
Diff. 12.5 3.0 12.0 … … … … … 9.2
The upper course of the Soane being in some places confined, and exposed to furious gusts from the gullies of the Kymore hills, and at others expanding into a broad and flat valley, presents many fluctuations of temperature. The mean temperature is much above that of the lower parts of the same valley (below Tura), the excess amounting to 5.4 degrees. The nights and mornings are cooler, by 1.2 degrees, the days hotter by 10 degrees. There were also 10 degrees increase of range during the thirteen days spent there; and the mean range from day to day was nearly as great as it was on the hills of Bengal.
There being much exposed rock, and the valley being swept by violent dust-storms, the atmosphere is drier, the mean saturation point being .454, whereas in the lower part of the Soane's course it was .516.
A remarkable uniformity prevails in the depression of thermometers exposed to nocturnal radiation, whether laid on the earth, grass, or freely exposed; both the mean and maximum indication coincide very nearly with those of the lower Soane valley and of the hills. The temperature of tufts of green barley laid on the ground is one degree higher than that of short grass; Argemone and Calotropis leaves maintain a still warmer temperature; from the previous experiments the Argemone appeared to be considerably the cooler, which I was inclined to attribute to the smoother and more shining surface of its leaf, but from these there would seem to be no sensible difference between the radiating powers of the two plants.