286 FRAGMENTS OF SCIENCE 



8 oz., 4 oz., and 2 oz. of gun-cotton respectively. The 

 gun and the four rockets constituted a series, and eight 

 series were fired during the afternoon of the 17th. The 

 observations were made from the "Vestal" and the "Gal- 

 atea," positions being successively assumed which per- 

 mitted the sound to reach the observers with the wind, 

 against the wind, and across the wind. The distance of 

 the "Galatea" varied from 3 to 7 miles, that of the 

 "Vestal," which was more restricted in her movements, 

 being 2 to 3 miles. Briefly summed up, the result is that 

 the howitzer, firing a 3-lb. charge, which, it will be re- 

 membered, was our best gun at the South Foreland, was 

 beaten by the 12-oz. rocket, by the 8-oz. rocket, and by 

 the 4-oz. rocket. The 2-oz. rocket alone fell behind the 

 howitzer. 



It is worth while recording the distances at whioh some 

 of the sounds were heard on the day now referred to: 



24 out of 40 sounds heard 



5 

 18 



3 

 19 " 



The day was cloudy, with occasional showers of driz- 

 zling rain; the wind about N.W. by N. all day; at times 

 squally, rising to a force of 6 or 7, and sometimes drop- 

 ping to a force of 2 or 8. The station at Leigh excepted, 

 all these places were to leeward of Shoeburyness. At 

 four other stations to leeward, varying in distance from 

 15% to 24% miles, nothing was heard, while at eleven sta- 

 tions to windward, varying from 8 to 26 miles, the sounds 



