midday
`` One minute past five , '' replied Gideon Spilett directly . They had now only to calculate the operation . Nothing could be easier . It could be seen that there existed , in round numbers , a difference of five hours between the meridian of Washington and that of Lincoln Island , that is to say , it was midday in Lincoln Island when it was already five o'clock in the evening in Washington . Now the sun , in its apparent movement round the earth , traverses one degree in four minutes , or fifteen degrees an hour . Fifteen degrees multiplied by five hours give seventy-five degrees . Then , since Washington is 77deg 3 ' 11 '' as much as to say seventy-seven degrees counted from the meridian of Greenwich which the Americans take for their starting-point for longitudes concurrently with the English -- it followed that the island must be situated seventy-seven and seventy-five degrees west of the meridian of Greenwich , that is to say , on the hundred and fifty-second degree of west longitude .