Bohemia belongs to the watershed of the Elbe, which rises within the territory and receives on the right the Iser and the Polzen, and on the left the Adler; the Eger with its affluent the Tepl; the Biela and the Moldau. But the principal river of ~~ Bohemia, from every point of view, is the Moldau (Czech _Vltava_), not the Elbe. A glance at the hydrographic structure of Bohemia, which is of such a striking regularity, shows us that the Moldau is the main stem, while the Elbe and the other rivers are only lateral branches; moreover, the Elbe below Melnik, the point of its confluence with the Moldau, follows the general direction of the Moldau. Besides, the Moldau is the principal commercial artery of the country, being navigable below Budweis, while the Upper-Elbe is not navigable; its basin (11,890 sq. m.) is twice as great as that of the Elbe, and its width and depth are also greater. It has a length of 270 m., 47 m. longer than the Upper-Elbe, but it runs through a deep and narrow valley, in which there is neither road nor railway, extending from above Budweis to about 15 m. south of Prague. The Moldau receives on the right the Luzniza and the Sazawa and on the left the Wottawa and the Beraun. The Beraun is formed by the union of the Mies with the Radbusa, Angel and Uslawa, and is the third most important river of the country. There are only a few lakes, which are mostly found at high altitudes. _Climate._--Bohemia has a continental, generally healthy climate, which varies much in different parts of the country. It is mildest in the centre, where, e.g. at Prague, the mean annual temperature is 48.5 deg. F. The rainfall varies also according to the districts, the rainy season being the summer. Thus the mean annual rainfall in the interior of Bohemia is 18 in., in the Riesengebirge 40 in., while in the Bohmerwald it reaches 60 to 70 in.