The temperature of the air was below 40°, in January, on 10 nights; in February on 3 nights; in March on 2 nights; and in December on 8 nights. Therefore the temperature was below 40° on 23 different nights in the year. The yearly range of temperature was 63°·5. At Sarona the temperature was below 40° on only 3 nights during the year; the lowest in the year, 38°·0, occurred on March 19th. The yearly range of temperature at Sarona was 65°.
The range of temperature in each month is shown in column 7, and these numbers vary from 25°·5 in January, to 49°·5 in March. At Sarona the range of temperature in each month varied from 22° in July, to 52° in March.
The mean of all the highest by day, of the lowest by night, and of the average daily ranges of temperature, are shown in columns 8, 9 and 10 respectively. Of the high day temperatures, the lowest, 50°·8, is in January, and the highest, 89°·3, in August. At Sarona, of the mean of all the highest by day, the lowest, 62°·3, is in January, and the highest, 87º·1, in both August and September,
Of the low night temperature, the coldest, 40°·3, is in January, and the warmest, 62°·6, in July. At Sarona, of the low night temperature, the coldest, 45°·6, is in February, and the warmest, 68°·8, in July. Of the average daily range of temperature, as shown in column 10, the smallest, 10°·5, is in January, and the largest, 27°, in August. At Sarona, of the average daily range of temperature, the smallest, 15°·7, is in January, and the largest, 23°·4, in May.
In column 11 the mean temperature of each month is shown, as found from observations of the maximum and minimum thermometers only. The month of the lowest temperature is January, 45°·5, and that of the highest, October, 79°·3. The mean for the year is 63°·7. At Sarona the lowest in the year was January, 54°·4, and that of the highest August, 77°·7. The mean for the year at Sarona was 65°·9.
The numbers in columns 12 and 13 are the monthly means of a dry and wet bulb-thermometer, taken daily at 9 a.m., and in column 14 the monthly temperature of the dew-point, or that temperature at which dew would have been deposited at the same hour is shown; the elastic force of vapour is shown in column 15. In column 16 the water present in a cubic foot of air is shown; in January and February was as small as 3 grains, and in July as large as 512 grains. In column 17 the additional weight required for saturation is shown. The numbers in column 18 show the degree of humidity, saturation being considered 100; the smallest number indicating the driest month is 42, in May, and the largest, 86, in January. The weight of a cubic foot of air under its pressure, temperature, and humidity, at 9 a.m., is shown in column 19.
The most prevalent winds in January were E. and S.W., and the least prevalent were N. and S.E. In February the most prevalent was S.W., and the least were N. and S. In March the most prevalent were S.E. and W., and the least were N.E. and N.W. In April the most prevalent was N.W., and the least were N. and S. In May the most prevalent
