BRITISH MEAN TEMPERATURES. 
49 
nection which exists between disease and temperature, and have 
shown by means of curves, drawn according to the percentages 
of deaths above or below the mean number for the year, the 
oscillations which occur as the weather changes. Some of 
these curves, which have been drawn for all the disorders for 
which the Registrar-Greneral’s returns furnish data, are ex- 
ceedingly well marked. 
The curve for diseases of the respiratory organs shows 
a maximum during the first two weeks of January, and a 
minimum in the last two weeks of August ; while the curves for 
dysentery, diarrhoea, and cholera show that during the greater 
part of the year deaths from these causes are very much below 
the average for the year ; but that during July, August, 
and September the percentage of deaths above the mean 
increases with frightful rapidity. These are the most 
strongly marked of the curves ; but, in nearly all, some 
relationship may be traced between the climate and the 
number of deaths. Even suicides, murders, and homicides, as 
well as such diseases as delirium tremens, show that they are 
amenable to certain climatic influences, and exhibit regular 
periods of maximum and minimum intensity. Of delirium 
tremens, Messrs. Buchan and Mitchell say : 44 Deaths from this 
cause have a well marked annual curve — it rises above its 
average in the middle of May, attains its absolute maximum in 
the latter part of July, thereafter falls to the average in the last 
week in September. Its absolute minimum is during the first 
half of December ; and it continues below the average from 
October to the middle of May, with the singular exception of the 
Christmas and New Year period, when there occurs a short 
continued secondary maximum.” This secondary maximum 
is probably due to disturbing influences other than the 
weather. 
Such are the main characteristics of the temperature of the 
British Isles for each month of the year ; and it only remains to 
say that the means from which this paper is compiled are those 
just published in the 44 Quarterly Weather Report,” pt. 3, 1875; 
that they are derived from the maximum and minimum obser- 
vations made at different stations over the country ; and that they 
extend, as a rule , over a period of four years. Such a period is, 
it is well known, generally considered to be too short for the de- 
duction of perfectly reliable temperature means ; but whatever 
deficiency the present observations have in regard to length of 
time, is probably largely compensated for by taking into con- 
sideration the fact that they refer to a period which has only 
just passed, the superiority of the instruments used, and their 
better exposure and uniformity. Besides, in addition, it has 
been proved by incontestable evidence that every marsh that is 
NEW SERIES, VOL. III. — NO. IX. E 
