The day of the summer solstice is implied as the time of this observation. Proceeding upon this assumption Professor Rafn[21] calculated that, in the 13th century, on the 25th of July, the sun’s declination was 17° 54′ N., and the inclination of the ecliptic 23° 32′. Gardar was in 60° 55′ N. At the summer solstice, the height of the sun there, when in the N.W., was 3° 40′, equivalent to the midnight altitude of the sun on St James’s day (July 25th) in latitude 75° 46′, which is the latitude of Cape York. The Norse explorers, starting from Kroksfjord (Wolstenholme Sound) sailed into the north water of Baffin’s Bay. They then went northwards from about 76° for three _doeg_, 108 miles each _doeg_. This brought them some distance up Smith Sound, beyond 80°. They saw many islands and glaciers and then returned southward for three _doeg_, coming to some islands, possibly the Cary Islands. Thence a long day’s pull brought them to Kroksfjord. Seven hundred years afterwards, a lofty cairn, built by unknown hands, was found on Washington Irving Island in Smith Sound. It is not to be supposed that this was the only voyage of the kind that was undertaken by the Norsemen because it is the only one of which any record has reached us. These enterprises must surely have constantly succeeded one another, with a view to discovering fresh fishing grounds. They must have been more or less continuous for two centuries at least. At its most flourishing time the Norse colony in Greenland numbered about 2000 souls in 280 homesteads. There were 12 churches in the East Bygd (the ruins of five have been found), and four in the West Bygd, and one monastery. But at the end of the 13th century the prosperity of the colony began to wane. Its existence depended upon annual intercourse with Norway, and communication began to be more and more irregular. There is a list of Bishops, but latterly few appear to have visited their See. In 1341 a bailiff of the bishopric named Ivar Bardsen was sent to Greenland to report upon the state of affairs. He found the West Bygd deserted. Ivar Bardsen made a valuable report, describing the topography of the East Bygd settlements in detail, and giving 54 place names[22]. In 1347 a Greenland ship arrived in Iceland with 18 men on board. She had been to Markland to cut wood, and had been driven out of her course by a storm[23]. In the same year King Magnus of Norway and Queen Blanche left 100 marks to Gardar Cathedral. But two years later the Black Death decimated the Norwegians, and soon afterwards all intercourse with Greenland ceased. Norway was a province of Denmark for more than four centuries.