APRIL 26, 1901.] 
mense guns are fired at ranges which re- 
quire the rotation of the earth to be taken 
into account, and with a precision which 
considers the difference in density of the 
air at the top and at the bottom of the bore, 
whose war ships are armored with the latest 
discoveries of metallurgy, their turrets 
turned and their guns loaded and trained 
by the electric current, and their evolutions 
directed by invisible vibrations of ether— 
surely a society thus armed has nothing to 
fear from any barbarian peril, be it yellow 
or be it black. 
Civilization. is safeguarded by science not 
only from the irruption of savage hordes, 
but also from the invasion of disease, from 
such epidemics as that which in the middle 
of the 14th century swept away more than 
half the population of England, and twenty- 
five millions of people in Europe. To-day 
when the plague appears in San Francisco or 
in London, it excites little more alarm than 
Gibraltar would feel at the assault of the 
Moor. By the simple remedy of vaccina- 
tion science has saved in each generation 
of the century more lives, it is said, than 
were lost in all the wars of Napoleon. 
Among civilized nations within the last 
five centuries the death rate has been so 
lowered that the average duration of human 
life has nearly doubled. Medicine no 
longer attacks disease with charm, exorcism 
and nostrum ; she obtains her weapons from 
the armory of science. From chemistry 
‘she brings a pure materia medica, new com- 
pounds, new processes, new methods of 
diagnosis, and anesthetics which have made 
surgery painless. From physics she ob- 
tains the appliances of electro-therapeutics, 
a delicate cautery, and the Rontgen ray, 
used by physicians in almost every town 
of size in lowa within less than half a de- 
cade of its discovery. 
The debt of the healing art to the sci- 
ences of the biologic group is so vast that I 
will select but one, bacteriology, for illus- 
SCIENCE. 
645 
tration. It is to no lucky chance that the 
discovery is due of man’s most subtle and 
deadly foes, the bacteria. The work of 
Pasteur, the pioneer, and of his illustrious 
followers, is marked by the most thorough 
and painstaking investigation, and the most 
searching and rigid tests. It is by the ap- 
plication of the scientific method that the 
enemy has been unmasked, his ambuscades 
and chosen places for assault discovered 
and rational methods for his destruction 
demonstrated. It is men of science who 
have organized the victory of medicine to- 
day over diphtheria, rabies and the plague, 
over the venom of the snake and all the 
diseases to which serum therapathy is suc- 
cessfully applied. And where the bac- 
teriologist cannot as yet supply a specific 
for disease, he can often point the way to 
its prevention. When the access to the 
human system of the germs of typhoid and 
cholera by drinking water is demonstrated, 
Hamburg builds its filter beds at a cost of 
$2,280,000 and Chicago expends $33,000,- 
000 upon the drainage canal. And so with 
the great white plague, tubercular con- 
sumption. Science has proved the lurking 
places of the contagium in the sputum, and 
its carriage in the air we breathe, and rein- 
forced by the high moral sense of our 
people, she is fast making it as impossible 
for the consumptive to spit on the pave- 
ment unhindered as for the smallpox 
patient to walk unarrested down our 
streets. 
And who can estimate the number of 
lives now saved in each generation by 
aseptic surgery? So long as putrefaction 
was held, as by Liebig, to be due to the 
action of the oxygen of the air, no remedy 
for it could be suggested ; but when once its 
bacterial origin was proved, the step was 
inevitable to those precautions which have 
rendered safe and successful the ene TOE 
operations of modern surgery. 
Micro-biology extends her gis also over 
