182 
POPULAE SCIENCE EEYIEW. 
that scarcely any one conld be met who^ on inquiry, would not 
be found with the back of the throat unduly red, and the 
tonsils large ? Why, in a given village or town, shall the 
medical men be summoned on some particular day to two or 
half-a-dozen places perhaps at once, to visit children with 
croup ? What is the reason that many cases of sudden death, by 
so-called apoplexy,^'’ crowd together into a few houi’s ? Why 
in a given day or week are shoals of the aged swept away, while 
the young live as before ? These are questions which are 
above the answering of curative and preventive medicine 
alike. Curative medicine, if her inteiqjreter be honest, at the 
name of them, stands abashed ; and preventive medicine says, 
if her interpreter be true, The questions are as yet out of my 
range^^^ 
Still, we are not altogether ignorant : some circumstances 
appear to be followed by effects so definite, that we may almost 
consider we have them before us, in an obscure picture of cause 
and effect. It will be profitable to look at this picture, and try to 
make it out from various points of view ; but I must confine 
myself to one point now, viz., to the simple influence of a loio 
wave temperature on life. 
If we carefully observe the fluctuation of the thermometer 
by the side of the mortality of the nation at large, no very 
remarkable relationship seems to be traceable between the 
one and the other. But if, in connection with the mortality, 
care be taken to isolate the cases, and to divide them into 
groups according to their ages, a singular and significant 
series of facts follow, which show that after a given age 
a sudden decline of the temperature influences mortality by 
what may be considered a definite law. The law is, that 
up to the age of thirty years variations of temperature exert 
no influence on the mortality of the population generally; 
but after the age of thirty is reached, then a fall of tempera- 
ture, which is sufficient to cause an increased number of deaths, 
acts in a given manner, — as it may be said in waves or lines 
of intensity, according to the years of the people. If we make 
these lines nine years long, we discover that they double in 
force at each successive point. Thus, if the fall in the tempe- 
rature be sufficient to increase the mortality at the rate of one 
person of the age of thirty, the increase will run as follows : — 
One death at thirty years of age. 
Two deaths at thirty-nine years of age. 
r our deaths at forty-eight years of age. 
Eight deaths at fifty-seven years of age. 
Sixteen deaths at sixty-six years of age. 
Thirty-two deaths at seventy-five years of age. 
Sixty-four deaths at eighty-four years of age. 
