June 16th.—I spent the day inside the balloon, where, with the help of ten seamen, I put another coat of varnish on the seams.
The Virgo, which has been waiting four days in her prison of ice, can at last start to-day; in fact, her time is up, for she must be at Tromsö before the 20th of June, otherwise Andrée will have to pay a heavy fine for every day’s delay.
It took two days to re-varnish the seams. On the 18th of June all the air in the balloon was let out so as to prepare for the inflation by gas; the net is again placed over it, and the valves inserted. The inflating tubes are brought under the floor of the shed and connected with the nozzle through an opening made in the centre of the floor. The inflation by gas began at seven on the morning of the 19th of June.
Stake, the engineer, is superintending the manufacture of the hydrogen. It is produced by the action of sulphuric acid diluted with water on iron. The acid, the strength of which is 60°, is brought in iron drums, each containing 220 lbs. We have 176,369 lbs. of it, and 66,138 lbs. would suffice to inflate the balloon.
The gas apparatus was constructed at Stockholm from well-known designs. The acid is raised, by means of a hand pump, into a mixing tank “C,” made to hold 2,817 pints, and meanwhile water is introduced which reduces the contents to a solution representing about 16°.
The acidulated compound passes thence into two lead-lined generators “G,” containing the iron, which is dropped in as required through a hopper placed half-way up, and closed with a hydraulic joint. The iron shavings put into the outside part of this hopper are pushed down, thus forcing the shavings in the inner part into the generator. Each generator is closed by a lid with a hydraulic joint. The apparatus is freed from the mud deposited at the bottom by means of a self-closing cock.
The hydrogen produced by this reaction passes into a purifier “L,” filled with coke, and provided with a tapering grate; through this grate the gas makes its way into the washing compartment, and passes through the column of coke in which is circulating the water that falls from the rose attached to the top.
SKETCH OF THE CONSTRUCTION OF THE HYDROGEN GAS-PRODUCING APPARATUS.
The overflow runs away through a pipe at “U” at the bottom of the apparatus. A steam-pump feeds the purifier and the mixing tank with sea-water, which, by the way, is quite suitable for this process.