Unfortunately the Commodore had only ships of deep draught--vessels that could not cross the shoal water over the bars of Mexican streams. And the number of ships was small, so that when ordered to blockade the coast he was not able to do so for several months. As late as October, 1846, his force was “barely sufficient to close the ports of Vera Cruz and Tampico.” By October, however, he had three schooners and the shoal-draught steamer _Vixen_, and this force was subsequently increased to three light steamers and seven gun-boats, the whole flotilla carrying seventeen cannon. Meantime, on August 7th, an attempt was made on Alvarado, an important port southeast of Vera Cruz. The ships were unable to get over the bar. On August 15th, a force was collected before Tuspan, but the brig _Truxton_ grounded within reach of the shore-batteries and was captured, and the attack failed. On October 16th a second attack was made on Alvarado. The steamer _Vixen_ towed in the schooners _Bonita_ and _Reefer_ and a vigorous attack was made, but the steamer _McLane_, towing the _Nonita_, the _Petrel_, and the _Forward_, grounded. The steamer _Mississippi_ had bombarded at long range the enemy’s works, but it was ineffectual, and this attack failed. The failures created a deal of dissatisfaction in the United States, but it is a fact that Commodore Conner had a wretched outfit for the work. The small steamers were especially bad. [Illustration: Commodore Perry’s Expedition Taking Possession of Tuspan. _From a lithograph of a drawing by Lieutenant H. Walke, U. S. N._] On the day following the Alvarado failure Commodore Conner sent an expedition under Captain Matthew Calbraith Perry, then commanding the _Mississippi_, against Frontera. Perry was afterward distinguished for opening Japan’s ports to American commerce. He had with the _Mississippi_ in his attack on Frontera the steamers _Vixen_ and _McLane_, and the schooners _Bonita_, _Reefer_, _Nonita_, and _Forward_, and he carried two hundred marines, besides ample crews. Frontera was an important port, because the river that flows in the gulf there is the dividing line between the Yucatan peninsula and Mexico proper. Moreover, Tabasco was an important city lying some distance up the river. The Mexicans had a considerable fleet of merchant vessels in this river--two river steamers, in fact, besides five coasting schooners, a brig, a sloop, and a lot of small barges. Captain Perry made a dash over the bar with the _Vixen_ and two schooners, when he reached the mouth of the river. The Mexican fleet inside were taken almost unawares--there was, at any rate, no time to escape, and the fire of the land-batteries did no damage to the Americans. After the capture of the shipping the forts and town surrendered. [Illustration: Matthew Calbraith Perry. _From an oil painting at the Naval Academy, Annapolis._]