214 
Second. — Where it is partially found amongst popula- 
tions. I lived for four years in close proximity to the 
most populous part of the village of Eccles. This village 
contains a population of two or three thousand. Its sani- 
tary condition is most unsatisfactory. Its mean height 
above the sea is about 112 feet. It is situated about four 
and a half miles west of Manchester. I made observations 
of ozone at that station for more than three years, and the 
amounts detected with Dr. Moffat’s test papers were con- 
siderably below those obtained by Mr. Vernon, F.RA.S., at 
Old Trafford, two miles nearer Manchester, but where the 
population is less dense and the sanitary condition far 
superior. I infer, then, that density of population, with 
imperfect sanitary regulations, either destroys ozone or 
prevents its formation. 
Third. — Where variable amounts of ozone are found out 
of large towns. Ozone is detected in considerable quan- 
tities on the sea-coast, and in rural valleys far removed 
from towns ; but it is well known that far larger amounts 
are detected in elevated districts, as on hills and mountains. 
The amounts detected by Mr. Heap, of Hoy ton, near Oldham ? 
and Mr. Thompson, of Wilmslow, far exceed anything that 
is found on low rural lands or near the sea. Mr. Heap’s 
station is 544 feet above the sea, and Mr. Thompson’s 251 
feet. Mr. Samuel Marshall, of Kendal, also writes — “ I am 
much surprised at the results of experiments made by my 
friend Edward Hay ton, at his residence, High House, which 
is about 7J miles N.W. from Kendal, and two miles nearly 
west from the railway station at Windermere — 636 feet 
above the sea level. * * * No material interruption of 
hills between it and the sea, Morecambe Bay, which lies a 
little west of south. The amount of ozone collected here is 
surprising, being nearly three times the quantity of that at 
Kendal. It may be said that sea breezes conveying ozone 
from the Irish Sea meet with no material obstacle before 
