It remained for Dr. Gustav Storm to point out the correct way of utilizing the data supplied. Assuming the instructions in the Kristinret to apply to an observation recorded of an earlier day, and assuming the passage to mean that the sun set at the precise moment of ‘eykt’, the amplitude, or distance from the west at setting, of the sun on the shortest day in Wineland was 37½. We may assume, as the observer would have been looking across the land, that the lower edge of the sun was at least 19′ above the actual horizon, and this being so no allowance for refraction or dip of the horizon need be made before working out the formula:—sec : lat : = sin : amp : cosec : decl. Professor Turner, of the Oxford University Observatory, has kindly supplied me with the corrected declination for the year A.D. 1000, viz: 23° 34′ 8″. We need not trouble about the seconds, as we know neither the precise moment of the solstice nor even the year with certainty; omitting these the problem works out as follows:— log sin : amplitude : 9·784447 log cosec : declination : 10·398140 ————————— log sec : latitude : 10·182587 ========= The latitude therefore would be about 48° 57′ N. This, however, correctly understood, gives only the northern limit beyond which the observation could not have been made. It might be argued that the refinements enjoined in the Kristinret were not likely to have been in operation in these primitive times. There seem to have been eight day-marks, two of which represented midnight and noon respectively, and it would seem more natural therefore for men who attached no particular importance to the hour of 3 p.m. such as was subsequently associated with the time of nones, to divide their horizon into equal parts, which would serve, at any rate at the equinoxes, accurately for 6 a.m. and p.m. and mid-day, while dagmál and eykt would occupy the points midway between the others, and stand, less accurately, for 9 a.m. and 3 p.m. The answer to this criticism probably is that it was found necessary to divide the day into equal watches: anyhow, such an interpretation cannot be correct, for an amplitude of 45° would give a latitude of 55° 34′ up to which this bearing would be visible, and this would be too near the latitude of Greenland to be remarkable, while nothing is clearer than that the writer of the passage was endeavouring to record a marked and surprising difference from the length of the winter day to which Greenlanders were accustomed.