ON NINE BALLOON ASCENTS IN 18G3 AND 18G4. 



317 



TiSTE OF ViBEATION OF A HORIZONTAL MaGNET. 



June 27, 1864. 

 feet 



seconds. 



At the Alliance Inn, Brookland, at 1*" a.m., on June 28, 30 vibrations of 

 the same horizontal magnet were observed as foUows : — in 47'"2, 47''2, 47^*2, 

 46'-5, and in 47'-2. 



A^^f|ust 29, 1864. 

 At the Eoyal Observatory, Greenwich, at noon, 



30 vibrations of a horizontal magnet was 



30 



30 



30 



5> 





» 



}> 



seconds. 

 49-0 



48-5 

 48-8 

 49-0 



feet. 



seconds. 



At 4 41 30 at 13,375 there were 26 vibrations of a horizontal magnet in 46-8 

 „ 4 45 „ 14,293 





30 



28 









>} 



52 

 49-5 



„ 4 47 30 „ 14,317 



On June 27, at the average height of 3350 feet, the magnet vibrated in 1-635 



On the ground at Brookland, one vibration was 1"698 



On Aug. 29, at the average height of 14000 feet, the magnet vibrated in 1-767 

 At the Eoyal Observatory, Greenwich, one vibration was 1-627 



Therefore the time of vibration seems to be somewhat longer in the higher 

 atmosphere than on the ground ; the difference being somewhat greater than 

 as shown above in consequence of the higher temperature of the earth. 



General Observations. 



August 31, 1863. 



At 6" 21" 30' p.m., at 6404 feet. The Tyne was visible almost to its source. 



At 6^ 27"" p.m., at 7790 feet. Newcastle seen. 



At 6'' 33" 30' p.m., at 7690 feet. Wind was felt in our faces. 

 . At 6" 37'" 30' p.m., at 6898 feet. Losing sight of the sun. Travelling 

 along a hne of railway in the direction of Durham. Wind gentle. Fields 

 seen with sheaves of corn through a break in the clouds. 



At 6*^ 57" 30' p.m., at 1200 feet. Earth seen faintly ; can see furnaces 

 and tramways ; Durham Minster in sight on a hiU ; Leanside Junction visible. 



At 6" 59"" p.m., at 840 feet. Going towards hills beyond Leanside, 



