83 '" Aerial Navigation. 



out the barometer stood at 28 in. 3 I'm. ; and^, at the height 

 to which be had attained, it fell to 23 in. Between the 

 ina^s of clouds which rolled over him in an awful manner, 

 like mountain*, t'rc thermometer fell suddenly to 5 degree* 

 above zero. The balloon was whirled round and carried 

 forward with a most violent motion. No scientific experi- 

 ments could here be made, except a few observations in 

 rccard lo the manngement of a balloon ; such as the 

 simplest method of fixing the balloon at a determinate 

 helsht, and of securing it; also to calculate the velocity 

 of Its fall in a diagonal line on descending, and therebv to 

 ascertain the moment of its arrival at the earth, which is 

 always the most dangerous part in an aerial excursion. 

 M. Robertson v ill publish an account of these and of other 

 experiments. While hovering in the clouds, the aerial 

 traveller discovered below him a fir wood of great extent ; 

 he proceeded over it a mile in order to take advantage of the 

 first interval between the trees, and suffered himself to 

 descend in an open place, which was scarcely so large as 

 twice the diameter of the machine. That he might be 

 able to dispense with the dubious and dangerous assistance 

 of men in fastenina; the car, M. l^obertson employed a kind 

 of hooked and ors. In the middle of a thick wood, 20 

 vcrsts distant from Riga, he alighted alone ; and the bal- 

 loon was nearly emptied and folded up, when he saw a 

 shepherd and his two boys, whom he called to give him 

 their assistance, and who showed him the way. The ex- 

 cursion continued three quarters of an hour. Messrs. Von 

 Bcig, Blankenhagen, iMeyer and Schwarz,Tiad followed 

 the aeronaut speedily, to draw up the account- M. Ro- 

 bertson is justly entitled to the praise of having applied all 

 his aerial excursions to the purposeof scientific experiments, 

 and of throwing light, if possible, on experiments which all 

 his predecessors have rather involved in darkness. 



Jji/ the same. 



Vienna, October lo. 



On the 8th,, Professor Robertson undertook an aerial ex- 

 cursion here, with the best success, in the presence of their 

 imperial highnesses the archdukes and a numerous crowd of 

 spccla;ors. He. ascended from the Prater about a quarter 

 past five in the ;ifiernoon. lie rose to a considerable 

 iheio-ht, and sent down a parachute, which carried unhurt to 

 the Cvirth a livin;>- ilnirxaak This utiridl excursion is remark- 

 ijLie, on aecovuic of au experimcut Uiade by Profe53t|r Ro- 



bcrtaoxi 



