Imagens das páginas
[merged small][table]

The results of the above numerical elements may be summed up in the following terms: —

At equal meridional altitudes of the sun, the diurnal maximum of the intensity of solar rays is greater in Van Diemen's Land than it is in New South Wales.

In both the colonies the diurnal increase and decrease of such intensity has a different developement. Until 9 A. M., the increase of solar intensity in New South Wales is sudden and abrupt, and greatly exceeds in degree that of Van Diemen's Land. From 9 o'clock, however, the increase developes itself more rapidly and attains a higher degree in Van Diemen's Land than it does in New South Wales. In both colonies the increase of the intensity equally follows the increase of the sun's altitude from morning till noon; from noon till 2 or 3 o'clock, the intensity and the motion of the sun are in an inverse relation to each other; that is, as the sun is decreasing in altitude, the intensity increases.

The numerical elements further show that at equal meridional altitudes the diurnal maximum of the calorific effects which solar rays produce by absorption are greater in New South Wales than they are in Van Diemen's Land.

Again, the developement of such effects from morning till noon in one country, is the reverse of that which takes place in the other; that is, while in New South Wales the calorific effects are decreasing from 8 A. M. till 12, in Van Diemen's Land they are on the increase.

In the tables for both the colonies, the effects of solar rays do not show any relation to the altitude of the sun.

The application of the above results to farther inferences is singularly modified by the elements relative to the diaphaneity of the atmosphere in the two countries.

The observations connected with the inquiry into that diaphaneity, show that the difference between

« AnteriorContinuar »