BY THE PRESIDENT. 165 



reduce the perversions back again to physiological limits, and 

 health is restored. To this beneficial law we owe the maintenance 

 of the form and beauty of our race, in the presence of so much that 

 tends to spoil and degrade it. The effects of disease may be for 

 the third and fourth generation, but the laws of health are for a 

 thousand. Although this law of the vis medicatrix naturce has 

 been chiefly studied in human subjects, yet I think it may be 

 equally seen to act throughout the animal, the vegetable, and the 

 mineral kingdom, and the entire universe. In fact, I regard it as 

 a part of the universal law of perpetual circular motion, in one 

 case restoring a child to health, in another clothing the earth with 

 vegetation, in another restraining and regulating the stars and the 

 planets in their orbits. I shall not refer to Psychology ; but it has 

 been said: "The development of intellectual gifts has been by 

 some supposed to follow a law of increase, culmination, and decay 

 in races, strictly analogous to that which has been observed in 

 individuals." 



I ought not to pass over what is called the Germ Theory of 

 Disease, not only because it supports my theory, but because it is 

 of great practical use to us all, and besides, it affords a most inte- 

 resting study to the naturalist. I can best explain Avhat is meant 

 by the germ theory of disease by stating what is daily taking place 

 in Watford and in other towns. Many people make the following 

 experiment. They ventilate the public sewers into their houses. 

 They have pipes made ; one end is made to enter the drain, the 

 other ends in the bath or the housemaid's sink, or it is placed over 

 the cistern of the diinking water. Then they warm their houses 

 at night, so as to suck up the sewer gas, and when they are enjoying 



" Tired Nature's sweet restorer, balmy sleep," 



they breathe these gases ; and then, if disease comes on, they 

 wonder how they could have caught it ; and if they cannot find 

 a cause, they think that it is a sufficient explanation to say that 

 the disease is a dispensation of Providence. Sewage is very good 

 food, excellent food, for plants But if animals will partake of it 

 before it has gone the circle through the vegetable kingdom pre- 

 scribed by the laws of Nature, nothing but harm can result. Then, 

 perhaps, two doctors are consulted, and one says that sewer gas of 

 itself can create or originate fever ; the other doctor says that it 

 cannot, unless it carries with it the germs of some previous fever, — 

 that you can no more get a fever without the germs of a former 

 case than you can get an oak without an acorn. You here see how 

 intimately connected are theory and practice. Germs are theoretical 



