134 The Microscopic Germ Theory of Disease. By H. C. Bastian, 
tions as artificial tuberculosis and syphilis into that class of diseases 
under which are included such affections as typhus, typhoid, 
relapsing fever, cholera, measles, scarlet fever, small-pox, and other 
contagious fevers. Affections like artificial tuberculosis and syphilis 
might therefore have been placed with equal appropriateness in 
either of the divisions I have adopted. 
The treatment of the present part of my subject may be disposed 
of in a more summary manner than the last, principally because 
many of the facts and considerations which were advanced in refer- 
ence to virulent inflammations and their sequelae, and the presence 
of independent organisms in the altered fluids and tissues of the 
body, are also applicable to the question of the relation of such 
organisms to the more specific contagious fevers. 
The case to be made out in favour of the germ theory as 
applied to these latter fevers is also, in my opinion, much weaker 
than it is in respect to the virulent inflammations and their sequelae, 
since, although such contagious fevers have always been regarded 
as general and essentially " blood diseases," in only one of those 
occurring at all commonly in the human subject does it appear that 
anything like an independent living organism is to be met with 
in the blood. There is, therefore, here a prima facie inherent 
weakness in the whole theory, which I think a thorough exami- 
nation of the question will strongly tend to confirm rather than 
dissipate. 
The reasons relied upon in favour of the germ theory, as applied 
to these diseases, are of a purely a priori or theoretical nature, 
and such as I have already referred to. They are, in fact, based 
upon the assumed nature of contagium, and upon its assumed mode 
of increase within the body. How Httle conclusive such a priori 
reasons are, and how the facts may be otherwise explained, I have 
already endeavoured to show, and as the theory in its applicabihty 
to these diseases rests upon absolutely no positive evidence that I 
am aware of, I am compelled to leave a gap here, and pass on to a 
brief enumeration of the facts and considerations which seem to tell 
so strongly against the existence of any causal relationship between 
organic germs and these specific contagious fevers : 
1. The fact that, with two exceptions, no definite germs or 
organisms are to be met with in the blood of patients suflering 
from these diseases, during any stage of their progress. 
2. The fact that the virus or contagium of some of these 
diseases, whatever it may be, does not exhibit the properties of 
living matter. 
3. On the other hand, the virus of most of these contagious 
diseases with which definite experiment has been made, is most 
potent in the fresh state, whilst its power very distinctly diminishes 
in intensity as organisms reveal their presence more abundantly 
