The buoys will be thrown out at different points of the voyage of the balloon. A thirteenth, larger than the others, will be left at that point of the route that shall be the nearest to the geographical pole that can be reached by the balloon.
July 1st.—We then proceeded to estimate the ascending power of the balloon. It was calculated that it could carry 3,747 lbs. of ballast, including that part of the cordage intended to be used as ballast, and that it could keep up for a minimum period of thirty to thirty-five days. This period could be extended in case of need, by sacrificing the sails and other parts that had become useless, the car if necessary, and part of the guide-ropes, as the explorers could still take refuge on the hoop, to which was attached all their provisions and necessaries. In this manner nearly 1,763 lbs. of supplementary ballast could be obtained, which would increase the length of the voyage by twenty days.
The aeronauts could thus remain in the air for more than fifty days, and at the same time keep their food and the necessary apparatus and cordage. Thus their departure would take place under most promising conditions.
As to the point of landing, the chances seem to point most to Siberia, which offers a very large extent of land; next in order of probability comes Alaska, in North America. Andrée did not think that the balloon could be drawn towards Greenland, with its gigantic glaciers attaining to such great altitudes, as the surrounding lower strata of air cool rapidly by contact with this boundless frozen mass, and currents would be formed there that would radiate in all directions. Only the currents of the upper atmosphere would approach these regions; but the Andrée balloon always travels close to the earth, which is, moreover, another point in favour of its longevity. We need not fear, therefore, that the explorers will be lost in the glaciers of Greenland.
THE MEMBERS OF THE EXPEDITION.
Variable winds may drive the balloon for several days over the ice-field and over the ocean, before it can meet with a spot favourable to its descent. We have already seen that it could keep up for more than fifty days; therefore, unless any serious accident or unforeseen delay occurs, there is every reason to hope that before this time the aeronauts will have set foot on some hospitable ground. If, owing to some unforeseen cause, they should be obliged to descend on the ice-field, they would have to return in the same way as Dr. Nansen.
He, after leaving his ship, the Fram, in company with Lieutenant Johannsen, remained for fifteen months on the ice-field with only three months’ provisions.