They followed this river east to Lake Chad , north around the western and northern shores of the lake and then south along its eastern shore .
In January 1900 Foureau and Lamy left Zinder , moving south - east towards the Komadugu Yobe River .
They followed this river east to Lake Chad , north around the western and northern shores of the lake and then south along Zinder 's eastern shore .
In January 1900 Foureau and Lamy left Zinder , moving south - east towards the Komadugu Yobe River .