are sufficiently familiar now-a-days, as they doubtless were in remoter times, is an agency they will not accept of as more likely to have burst asunder the rocky barriers of the lake and given exit to its waters. Humboldt or Jacquemont could probably have solved this interesting question. It is remarkable that in no part of the valley are fossil shells of aquatic races to be found, a circumstance sufficiently curious when taken in combination with the opinion of the former state of the country. Dr. Buchanan seems to have assented to the popular notion on the subject, without offering an explanation of his views. It is however certain, that if the narrow passage through which the river now flows did not at any previous time exist, the tract above it, which includes the whole valley, must have been a large lake, formed by the pent up waters of the surrounding hills, which now form the Bishomutti and Bagmutti river, with the innumerable tributary streams. Not a drop of water finds exit from the valley, save by this one narrow outlet, which pours its torrents in a southerly direction through the Mahabharat and lower ranges of hills, into the plains joining the Ganges near Mongbyr. The waters from the outer side of the northern, eastern, and western mountainous boundary of the valley, run east and west, the ormer falling into the Koosi, the latter into the Tirsoolgunga of the hills or Gunduck of the plains. The Koosis (for there are several streams bearing this name within the hills east of Cathmandu), unite their waters in the plains, and fall into the Ganges opposite Bhaugulpoor. The Tirsoolgunga reaching the plains at Tirbeni, flows through Sarun to the Ganges, joining the latter river at Hajeepoor.
Winds, Rain, Pressure of the Atmosphere and Temperature.—Not being at present prepared to give a specific account of the climate of the valley from personal meteorological observations, it will be sufficient to indicate generally its character as it has reference to the productions of the soil.
The most marked characteristics of the valley climate, are its extreme humidity and the irregularity of the winds, as to direction and intensity. The former of these circumstances, arises from the retention of so much water as is required for raising rice crops, together with an annual average fall of 50 inches of rain water; and the latter, from the high mountainous boundary girding the valley, by which the currents of air passing over their summits are prevented from reselling the valley's surface. It is often difficult to ascertain correctly from what direction the
