Gavarelle, F. A(loys) en. Essay on the navigability of the Lahn, Nahe, Mosel, Saar and other medium and smaller rivers. A contribution to a real action improvement. 128 pages, with a folded partial coloured map of the Lahn river. 19x11,1 cm. New semi-leather band (back faded and front lid slightly light edged). Koblenz, Lassaulx's printing house, 1806. Eckoldt: Rivers and canals p. 91. – The author, former Trier Hofrat and Chaussee Director, describes the ship's barricading of the Lahn, gives "information on the situation of the action of the Rhine, the Moselle, Saar, Nahe and Lahngegenägenden in general", follows a section on trade and products of the region, further on the trade with Bremen on Fulda, Werra and Weser as well as a description of the vessels in service and finally on the different water cargoes of different regions. To the Lahn map there is a division of the various lordships located on the Lahne and the mills existing between Ober-Lahnstein and Marburg. "The second navigability (the Lahn) was made possible with the reorganization of the Rhineland by the Rheinbund Act of 1806: the enlarged Duchy of Nassau could now make the Laah navigable up to the capital Weilburg. In 1810, the boat trip was officially opened." – A little spotted, slightly tanned. The map on slightly bluish paper with small tear. Titelbl. and another Bl. in the outer upper edge with deposited transparent adhesive strip.