 This change of plan , combined with further bad weather and la Peña 's insistence on marching only at night , meant the Allied force was now two days behind schedule . La Peña sent a message to Cádiz informing Zayas of the delay , but the dispatch was not received and on 3 March , Zayas launched his sally as arranged . A pontoon bridge was floated across the Santi Petri creek and a battalion sent across to establish a bridgehead prior to the arrival of the main force . Victor could not allow the Cádiz garrison , which still numbered about 13 @,@ 000 men , to make a sortie against his lines while he was threatened from outside , so on the night of 3 – 4 March he sent six companies of voltigeurs to storm the bridgehead entrenchments and prevent a breakout . Zayas 's battalion was ejected from its positions , with 300 Spanish casualties , and Zayas was forced to float the pontoon bridge back to the island for future use . 
