LIGHT, THE ORIGIN OF HEALTH. 743 
Geisler found that the blue and violet rays destroyed the 
typhoid bacilli, consequently typhoid patients should 
be in strong light, which has passed through jlue or 
violet-coloured glass. And they would tolerate that 
much better than sunglight. Koch states “that the 
tubercle bacilli is killed by the action of direct sunlight, 
in a time varying from a few minutes to several hours, 
depending upon the thickness of the layer exposed. Dif- 
fused light has the same effect, although a considerably 
longer time of exposure is required.”” Sternberg writes— 
“We may conclude, with Duclaux, that sunlight is one of the 
most potent and one of the cheapest agents for the destruc- 
tion of disease-producing bacteria; and that its use for 
this purpose is to be remembered in making practical 
hygienic recommendations. The popular idea that the 
exposure of infected articles of clothing and bedding in the 
sun is a useful sanitary precaution is fully sustained by 
scientific experiments.”’ 
All this, and much more I could quote, go to show that 
light gives health in many ways—that it gives health 
by strengthening and building up the body, that it 
preserves that health by killing disease-germs outside the 
body, and that it will penetrate the body and kill them 
there if sufficient opportunity is given. When my paper 
on “Sunny Tasmania for English Invalids,”’ was read in 
London, Sir W. Broadbent spoke of it as “a dream.” But 
there is nothing of the dream about it. If these statements 
are facts, they will apply to countries as well as individuals ; 
and the more sunshine a country gets, the more healthy 
will it be. 
England gets about 1100 hours of sunlight in a year. 
Tasmania gets about 2200, or double the English amount. 
If it is true that sunshine gives health, we must see it in 
our statistics. When I lived in England, the healthiest 
country district I could find was in Wiltshire, where the 
mortality was 15 per 1000. The statistics of all Tasmania 
show last year 11 per 1000, but this includes Hobart and 
Launceston; two seaport towns. Exclusive of these towns, 
there are 117,000 people living in the country and in the 
five mining towns scattered through the country. The total 
mortality in these was 9 per 1000. But of this number about 
one-third died of old age, and, as many accidents occur on 
the mines, 1 per 1000 died of violence. If we deduct these 
two causes, which no climatic conditions could avert, we get 
a mortality of 5 per 1000. Of these, again, about one-third 
are deaths under one year old, and mostly premature and 
