On April 17th Napoleon wrote to Davout, laying down the plan of action which he proposed in view of a Russian advance on Warsaw. The 60,000 men of the Saxon and Polish armies would, if possible, hold the line of the Vistula about Warsaw, but if overmatched must retreat on Glogau, where Davout would be able to come into line with them, while the main body of the Grand Army came up to the relief in two columns. He showed his confidence in his lieutenant by inviting him to examine and criticise the proposed plan. At this date the French forces were approximately stationed as follows, left to right. The Prussians were about Königsberg, and Davout’s six infantry divisions and a cavalry corps between Danzig and Thorn, all these forming what General Bonnal calls the Strategic Advanced Guard, under Davout. The 5th Corps was between Plock and Warsaw, the 7th Corps near Kalisch, 140 miles west of Warsaw, the 8th Corps between Glogau and Kalisch. The Bavarians (6th Corps) were marching from Glogau to Posen; the Army of Italy (4th Corps) was spread out over 100 miles of road in rear of Glogau; Ney was with the 3rd Corps about Frankfort on the Oder, eighty miles north-west of Glogau, and Oudinot with the 2nd about Berlin. As Bagration at Lutsk was some 250 miles from Warsaw, a study of the map will show that an offensive movement on his part could be opposed by at least equal numbers (the 5th, 7th and 8th Corps) in any case, apart from the 4th and 6th, which could be diverted on Warsaw, while a mass of over 200,000 men (Davout, Prussians, 2nd Corps, 3rd Corps and 2 cavalry corps) could oppose Barclay, besides the Guard. Towards the end of April Napoleon obtained fairly accurate information of the Russian emplacements. Six Army Corps and 3 divisions of reserve cavalry were extended from near Shavli in Courland to Slonim in Lithuania--a distance of nearly 250 miles. At Lutsk, over 200 miles from Slonim, and separated from it by the huge barrier of the Pinsk Marshes, were 2 Corps under Bagration, while slowly converging upon Lutsk were 5 divisions of infantry and 2 of cavalry. He could therefore calculate with sufficient certainty that his strategic deployment along the Vistula would not be interrupted. By May 15th the bulk of his forces were on the Vistula from Danzig to Warsaw. The Prussians were at Königsberg, the Austrians at Lemberg, the 4th Corps in reserve at Kalisch, the Imperial Guards marching in detachments across Germany. The whole mass, exclusive of non-combatants, amounted to nearly 450,000 men, of whom 80,000 were cavalry. It had with it, including its reserve parks, 1146 guns and howitzers, nearly 200,000 horses and draft animals, and probably 25,000 vehicles.