Faced with these difficulties, how are we to proceed? It is established that the Norsemen visited North America: the map of that country lies before us, awaiting the results of our survey. The evidence to hand is plainly of unequal value; we are in fact very much in the position of the cartographer, whose material ranges from the meticulously accurate work of the professional expert with his theodolite to the hasty compass traverses and sketches of the pioneer explorer fighting his way through trackless and savage wilds. The method by which the map-maker obtains the most satisfactory results from his material is, I think, one to be imitated here. To a framework made up of a number of points fixed with the utmost certainty of which science is capable, he adjusts the less trustworthy material, rejecting altogether that which cannot be brought into line with such facts as have been definitely ascertained. Any haphazard selection of separate items is bound to result in a considerable if not a cumulative error. So in the present case, unless we adhere inflexibly to what may be regarded as our fixed points, adapting that which fits, either wholly or in part, and inexorably rejecting the remainder, we shall be apt to jump to a conclusion and indulge in an arbitrary selection of whatever pieces of evidence happen to support it. A study of the results achieved by some earlier investigators of the subject presses this danger very forcibly upon one’s attention. Now perhaps some may be inclined to demur to the use of such an expression as ‘fixed points’ in this connexion, but there are really quite a number of statements standing out from the rest as facts which anyone who credits the sagas at all must regard as reasonably certain. These I will endeavour to set out before drawing any conclusions, in the hope that, studied apart from any question of where they may lead us, they may meet with general acceptance. 1. A line drawn about the 49th parallel of north latitude is fixed by the ‘eyktarstad’ observation as the northern limit of the area in which Wineland is to be sought. The passage, as we have seen, cannot be interpreted to mean that the sun set on the shortest day precisely at the point of eyktarstad. It would, in fact, be a coincidence difficult to credit if the sunset on a particular day corresponded with a mark arbitrarily fixed in Iceland for a wholly different purpose. The passage means, in fact, rather that the sun had _not_ set at the point in question; consequently to the south of this line we have an increasing probability for a considerable distance.