3 out of 40 sounds heard.

5. Epple Bay 22 miles S.E. by E. 19 out of 40 sounds heard.

6. Westgate 23 miles S.E. by E. 9 out of 40 sounds heard.

7. Kingsgate 25 miles S.E. by E. 8 out of 40 sounds heard.

The day was cloudy, with occasional showers of drizzling rain; the
wind about N.W. by N. all day; at times squally, rising to a force of
6 or 7 and sometimes dropping to a force of 2 or 3. The station at
Leigh excepted, all these places were to leeward of Shoeburyness. At
four other stations to leeward, varying in distance from 15.5 to 24.5
miles, nothing was heard, while at eleven stations to windward,
varying from 8 to 26 miles, the sounds were also inaudible. It was
found, indeed, that the sounds proceeding directly against the wind
did not penetrate much beyond 3 miles.

On the following day, viz. the 18th October, we proceeded to Dungeness
with the view of making a series of strict comparative experiments
with gun-cotton and cotton-powder. Rockets containing 8 oz, 4 oz, and
2 oz. of gun-cotton had been prepared at the Royal Arsenal; while
others, containing similar quantities of cotton-powder, had been
supplied by the Cotton-powder Company at Faversham. With these were
compared the ordinary 18-pounder gun, which happened to be mounted at
Dungeness, firing the usual charge of 3 lbs. of powder, and a syren.

From these experiments it appeared that the guncotton and
cotton-powder were practically equal as producers of sound.

The effectiveness of small charges was illustrated in a very striking
manner, only a single unit separating the numerical value of the 8-oz.
rocket from that of the 2-oz. rocket. The former was recorded as 6.9
and the latter as 5.9, the value of the 4-oz. rocket being
intermediate between them. These results were recorded by a number of
very practised observers on board the 'Galatea.' They were completely
borne out by the observations of the Coastguard, who marked the value
of the 8-oz rocket 6-1, and that of the 2-oz. rocket 5.2. The
18-pounder gun fell far behind all the rockets, a result, possibly, to
be in part ascribed to the imperfection of the powder. The
performance of the syren was, on the whole, less satisfactory than
that of the rocket. The instrument was worked, not by steam of 70
lbs. pressure, as at the South Foreland, but by compressed air,
beginning with 40 lbs. and ending with 30 lbs. pressure. The trumpet
was pointed to wind