764 
H. DE VARIGNY. 
they cannot tell. But the enumeration of the poet remains in¬ 
complete : microbes must be added to it. True, in Schiller’s 
time, microbes were not invented, and he must on that account 
be forgiven. 
Microbes strongly fear light, and especially the natural, that 
of the sun ; it is injurious and often fatal to them. This point 
is proved beyond doubt by nmnerons researches due principally 
to Arloing, Dnclaux, Buchner and Koch. And if these 
microbiologists had not discovered this fact during the last ten 
years, it would have been brought to the scientific world by a 
butcher who, some three years ago, discovered it in the follow¬ 
ing way: This gentleman, an American, in October, 1894, 
wrote to a well-known transatlantic bacteriologist, Mr. George 
Sternberg, to inform him that he had gathered a number of 
facts indicating a well-marked curative effect of the solar rays. 
Among them the most remarkable and the most suggestive was 
the rapidity of recovery in wounds and ulcers treated by the 
simple exposure to sunlight. This let us mention only in 
passing. 
As to the action of light upon pathogenous microbes, it 
has been studied in a sufficiently and repeatedly exact manner 
to prevent the slightest doubt as to the injurious influence that 
it possesses. It is marked to such a degree that Koch has been 
permitted to say and demonstrate that an exposure to the sun 
of several hours, or of several days at most, was sufficient to 
destroy the virulency of the bacilli of tuberculosis—the bacilli 
of Koch; and this general fact has been observed of other 
microbes, though naturally variations in the intensity of the 
action of the light may be observed according to the nature of 
the microbes, their general condition and other various circum¬ 
stances. 
Such being the case, it seems that light may have some thera¬ 
peutical influence ; and that there is reason to consider a new 
method of treatment, whose well-indicated name is phototherapy. 
In fact, phototherapy exists—even for some time back, under 
certain known or ignored forms, negative as well as positive. 
I 
