That Melas expected such a march is clear from a letter of his of May 23rd, dated from Savillan, to Lord Keith, which I have found in the "Brit. Admiralty Records" (Mediterranean, No. 22), where he says: "L'ennemi a cerné le fort de Bard et s'est avancé jusque sous le château d'Ivrée. Il est clair que son but est de délivrer Masséna."
Bonaparte did not leave Milan till June 9th: see "Correspondance" and the bulletin of June 10th. Jomini places his departure for the 7th, and thereby confuses his description for these two days. Thiers dates it on June 8th.
Lord W. Bentinck reported to the Brit. Admiralty ("Records," Meditn., No. 22), from Alessandria, on June 15th: "I am sorry to say that General Elsnitz's corps, which was composed of the grenadiers of the finest regiments in the (Austrian) army, arrived here in the most deplorable condition. His men had already suffered much from want of provisions and other hardships. He was pursued in his retreat by Genl. Suchet, who had with him about 7,000 men. There was an action at Ponte di Nava, in which the French failed; and it will appear scarcely credible, when I tell your Lordship, that the Austrians lost in this retreat, from fatigue only, near 5,000 men; and I have no doubt that Genl. Suchet will notify this to the world as a great victory."
The inaccuracy of Marbot's "Mémoires" is nowhere more glaring than in his statement that Marengo must have gone against the French if Ott's 25,000 Austrians from Genoa had joined their comrades. As a matter of fact, Ott, with 16,000 men, had already fought with Lannes at Montebello; and played a great part in the battle of Marengo.