EECENT EXPERIMENTS ON FOG-SIGNALS. 325 



to that instrument. Proceeding along the sea margin 

 at Flamboro' Head, Mr. Edwards states that at a dis- 

 tance of 1^ mile, with the 18-pounder previously used 

 as a fog-signal hidden behind the cliffs, its report was 

 quite unheard, while the 4-oz. rocket, rising to an eleva- 

 tion which brought it clearly into view, yielded a power- 

 ful sound in the face of an opposing wind. 



On the evening of February 9th, 1877, a remarkable 

 series of experiments were made by Mr. Prentice at 

 Stowmarket with the gun-cotton rocket. From the 

 report with which he has kindly furnished me I extract 

 the following particulars. The first column in the 

 annexed statement contains the name of the place of 

 observation, the second its distance from the firing-point, 

 and the third the result observed : 



Stoke Hill, Ipswich . 10 miles 



Melton . 



Framlingham . 



. 15 



. 18 



Stratford. St. Andrews . 19 



Tuddenham. St. Martin 10 



Christ Church Park. .11 



Nettlestead Hall . . 6 



&ildestone 

 Nacton . 



Rockets clearly seen and sounds 

 distinctly heard 53 seconds 

 after the flash. 



Signals distinctly heard. 

 Thought at first that sounds 

 were reverberated from the 

 sea. 



Signals very distinctly heard, 

 both in the open air and in a 

 closed room. Wind in favour 

 of sound. 



Reports loud ; startled pheasants 

 in a cover close by. 



Reports very loud ; rolled away 

 like thunder. 



Report arrived a little more 

 than a minute after flash. 



Distinct in every part of ob- 

 server's house. Very loud in 

 the open air. 



Explosion very loud, wind 

 against sound. 



Reports quite distinct mis- 

 taken by inhabitants for claps 

 of thunder. 



