62 KANSAS ACADEMY OF SCIENCE. 
true that every case of typhoid comes from a germ that is the seed of the disease, 
as surely as the acorn must precede an oak, and that the seeds of most cases are 
carried by drinking water. Marvelously evil results from apparently insignificant 
causes are not at all uncommon. 
Sewage, then, must be considered as the worst element in producing pollution; 
matter that should by no means be discharged into any stream used for a water- 
supply, or cast onto any watershed from which such a supply is gathered. 
Right here comes a serious problem for the sanitarian, the engineer, and the citi- 
zen. Water is not only necessary to us in our life processes, but is also one of 
our chief burden bearers; principally the carrier of our wastes, which it is essen- 
tial to remove from our environment. There is no more economical and sanitary 
way of transporting sewage than by means of water flowing in tight sewers. 
How can we continue this method and still preserve our sources of supply from 
sewage contamination? Or, if a supply is being polluted by sewage or other 
cause, how can we remove the polluting matter so as to furnish a safe supply ? 
The evils to be remedied are by no means new, and efforts have been made 
for fifty years or more to find a solution of the difficult problems. The density 
of the population of the older countries of Europe has forced these matters to the 
front, and more less successful attempts have been made to purify both sewage 
and water for public supplies, while stringent laws for the protection of streams 
and the collecting watersheds of reservoirs have been passed and enforced. For 
many years the chief incentive of those who advanced any new method of sewage 
treatment seemed to be the desire for a financial gain through the recovery from 
the sewage of itsvaluable constituents. Chemists can analyze sewage and figure 
the value of its nitrogen, phosphorus, etc., at current market prices, thereby 
estimating the total worth of yearly flow from any town. English estimates 
were placed at various figures, and the matter was gravely discussed by many of 
the leading scientists of the day. The value of London sewage was placed at 
from five million to twenty million dollars per year. A parliamentary commis- 
sion argued the matter in minute detail, and arrived at a value of four cents a 
ton as a safe and conservative estimate. These discussions stimulated the in- 
ventive mind, with the result that the English: government has granted 500 or 
more patents for the treatment of sewage. In many cases these proprietary 
methods were actually tried by companies formed to manufacture fertilizers for 
the open market, and so well were some of these enterprises exploited that they 
for a time paid the promoters, notwithstanding the fact that the product manu- 
factured had little real value—by no means commensurate with the price asked 
therefor. These patents involved mainly the method of chemical precipitation, 
and called often for the use of precipitating agencies that would render the 
effluent more foul than the sewage itself. 
Nor is it strange that the estimates of the fertilizing value of sewage should 
have turned attention to its utilization on land and the growing of crops through 
irrigation. Sewage farms sprung up all over England, and their financial success 
was much talked about, at first. But it was learned gradually that sewage farm- 
ing with raw sewage and sewage purification were two very different things, that 
ran opposite rather than parallel; that when worked for the crops the effluent 
was poor; and when managed to produce a good effluent, the crops would not 
balance the outlay. 
But the idea of financial gain has passed, and the underlying principle now is, 
as it should be, how to secure a good effluent, and so ' purify the sewage that it 
can be turned with safety into a running stream or on to a water-supply’s drain- 
age area. If, as a result of the method used, there is any return by way of a 
