The war of 1683 contributed to the increase of Vauban’s reputation. The siege of Luxemburg, in 1684, was carried on under his direction; and he here displayed an admirable presence of mind when discovered one evening by the enemy, in reconnoitring the works of the place. He instantly made a signal to them not to fire, and, instead of retreating, advanced towards them; they mistook him for one of their own officers, and having skirted the glacis, he retired slowly without exciting further suspicion. After having surmounted the many difficulties presented by the nature of the ground over which the attack was necessarily carried, the assailants attained the covered way. To drive the enemy out of its long branches, Vauban caused elevated parapets to be constructed on their prolongations, whence a plunging musketry-fire was thrown into the covered way, and the mass of its defenders were compelled to retreat; the few who remained concealed behind the traverses being gradually dislodged, as the crowning of the covered way was extended along the crest of the glacis. This siege was remarkable both for the difficulties which were overcome, and for the improvements made in the method of conducting an attack and protecting the troops employed in it. The new fortresses of Mont-Royal, Landau, and Fort Louis, together with extensive projects for the improvement of the canal of Languedoc, formed part of Vauban’s labours during the truce of Ratisbon. He likewise prepared a general project for the improvement and defence of all the ports, roadsteads, and coasts of France. To his exertions the French are indebted for the first general statistical account of their country, he having caused blank forms to be prepared and printed, which he distributed, to be filled up by the several intendants, governors, and other public functionaries with whom his frequent journeys through the country in the execution of his ordinary duties brought him acquainted. Louis XIV. afterwards caused these returns to be made generally throughout France.