about midday
There was another alternative . At high tide the boat would be afloat , and then , as the tide fell , he could keep her afloat until it was at its lowest . He could then embark , and be carried by the returning water straight on to the Straits of Minas , and up into the basin . He now made a calculation , and concluded that it would be high tide about midday , and low tide about six in the evening . If he were to embark at that time , he would have two hours of daylight in which to run up with the tide . He saw now that his whole plan was perfectly feasible , and it only remained to make preparations for the voyage . As the whole afternoon would be taken up in floating the boat down to low-water mark , the morning would have to be employed in making whatever arrangements might be necessary .