310 SCIENTIFIC BALLOONING. 



subject to some measure of guidance. The objections, however, to 

 thus retarding the balloon's motion and of fettering it to earth are 

 obvious, to say nothing of the consequences liable to ensue when such 

 a method of procedure is adopted across private property. 



The only direction in which we may look for any true navigation of 

 the air would seem to lie in the construction of aeroplanes, or floating 

 machines, operated by engines of great power and relatively extremely 

 small weight. Until such an engineering fact may have been accom- 

 plished the attention of aeronauts must be chiefly devoted to the study 

 of air currents, and the force and drift of prevalent winds, and with 

 regard to this a great deal of important information is already to hand 

 which should be duly noted. 



As far back as 1840 Mr. Charles Green, of whose skill as an 

 aeronaut we have already spoken, gave it as the result of his expe- 

 rience, gained in 275 ascents, that, under all circumstances, " at a 

 certain elevation, varying occasionally, but always within 10,000 feet 

 of the earth, a current from the west, or rather from the north of 

 west, invariably prevailed." Indeed, so firmly impressed was he with 

 the correctness of his observation in this respect that he proposed to 

 attempt a balloon flight from America to England, in which he was 

 confident of success. A very few years later we find Mr. Wise, the 

 then equally famous aeronaut on the other side of the Atlantic, seek- 

 ing with like confidence to put the same project into effect. 



But, naturally, where such constant winds prevail there must be 

 compensating currents found elsewhere, and in actual fact at varying 

 heights; but within a very few miles of the earth currents are often 

 to be met with blowing from every quarter in the heavens. 



It was during the memorable Nassau voyage already mentioned that 

 Mr. Green turned his knowledge of such currents to account in a 

 remarkable manner. Mght was coming on apace, and after passing 

 Canterbury with the sea close ahead it was noticed that their balloon 

 had come under the influence of a change of wind that would bear it 

 out to the German Ocean. But their skipper had already mapped out 

 the drift of accessible currents, and consequently rose to the height he 

 deemed needful, with the result that he at once regained his due 

 course. Mr. Monck-Mason writes of this that "nothing could exceed 

 the beauty of the maneuver or the success with which the balloon 

 acknowledged its influence." 



A very similar experience befell the present writer during the past 

 summer in a scientific excursion made in company with Dr. R. Lacnlan. 

 The ascent took place in the sheltered grounds of the Crystal Palace, 

 where the true force and direction of the wind could not well be esti- 

 mated, but at a few thousand feet a moderate current was reached 

 making steadily for the southeast. After a while, however, on descend- 

 ing near the ground for a few moments over Bromley, and again 

 rapidly ascending, the balloon was found considerably out of her course, 



