Morning was dawning when I went out of the forest. Empty space lied ahead. What is it? A lake? A river? No, it is not a lake, it's a river and a big one with riverside bushes and trees even several metres above the ice being brought down by a spring ice-drift. But what river can it be? The Ob? The Yenisei? Both these rivers flow north. The brushes are brought down to the right. So, the north is to the right. I am on the right bank. If I got to the Yenisei it would be the left bank. Thus it is the Ob! Quite often I had to solve similar geographic problems! Quite often I regretted my poor knowledge of the geography of Siberia!