&ECENT EXPERIMENTS ON FOQ SIGNALS. 209 
Shambles light-vessel, when a pressure of 13 Ibs. was 
employed to sound the syren, the rockets proved greatly 
superior to that instrument. Proceeding along the sea 
margin at Flamboro' Head, Mr. Edwards states that at a 
distance 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 elevation 
which brought it clearly into view, yielded a powerful 
sound in the face of an opposing wind. 
On the evening of February 9, 1877, a remarkable 
series of experiments were made by Mr. Prentice at Stow- 
market 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 . 
Melton 
10 miles Rockets clearly seen and sounds 
distinctly heard 53 seconds 
after the flash. 
Signals distinctly heard. 
Thought at first that sounds 
were reverberated from the 
15 
Framlingham .... 18 
Stratford. St. Andrews . 19 
Tuddenhani. St. Martin 10 
Christ Church Park. . . 11 
Nettlestead Hall 6 
Bildestone 
Nacton 
14 
Aldboro' 25 
Capel Mills 11 
Lawford ...... 15 
Signals very distinctly heard, 
both in the open air and in a 
closed room. Wind in favor 
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 obser- 
ver'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. 
Rockets seen through a very 
hazy atmosphere; a rumbling 
detonation heard. 
Reports heard within and. with- 
out the observer's house. 
Wind opposed to sound. 
Reports distinct; attributed to 
distant thunder. 
