The most serious disadvantages under which the colony of New South Wales labours, is in the drought to which it is periodically subject. Its climate may be said to be too dry; in other respects it is one of the most delightful under heaven; and experience of the certainty of the recurrence of the trying seasons to which I allude, should teach men to provide against their effects. Those seasons, during which no rain falls, appear, from the observations of former writers, to occur every ten or twelve years; and it is somewhat singular that no cause has been assigned for such periodical visitations. Whether the state of the interior has anything to do with them, and whether the wet or dry condition of the marshes at all regulate the seasons, is a question upon which I will not venture to give my decisive opinion. But most assuredly, when the interior is dry, the seasons are dry, and VICE VERSA. Indeed, not only is this the case, but rains, from excessive duration in the first year after a drought, decrease gradually year after year, until they wholly cease for a time. It seems not improbable, therefore, that the state of the interior does, in some measure, regulate the fall of rain upon the eastern ranges, which appears to decrease in quantity yearly as the marshes become exhausted, and cease altogether, when they no longer contain any water. A drought will naturally follow until such time as the air becomes surcharged with clouds or vapour from the ocean, which being no longer able to sustain their own weight, descend upon the mountains, and being conveyed by hundreds of streams into the western lowlands, again fill the marshes, and cause the recurrence of regular seasons. TEMPERATURE OF THE CLIMATE.