"The town of Colusa is built upon the old, or clay formation, and the people are entirely free from the so-called malarial influence. They are almost entirely free from chills, typhoid fevers, diphtheria, etc., but just at the lower end of the town there is evidence that the river at one time ran almost at right angles with its present course, and while the land is just as high, and very large oaks grew upon it, showing the formation to be very old--the span of human life taken as a measure--yet in digging and boring wells, as well as by the indigenous growth, the very great difference in the age of the formation was apparent. Upon this new formation an extension to the town was located, and among other buildings the county hospital was placed there. The patients and employes of the hospital all had chills for several years, until the physician-in-charge, Dr. W. H. Belton, noticed that the people generally who used water from wells on this newly-made land had chills, while the others had not, and caused pipes from the town waterworks, into which river water was pumped, to be laid to the hospital. There was an _immediate_ change. At the commencement of the use of river water, there were some forty persons in the hospital, all with chills, but since the building has been almost entirely free from it. There could be no more conclusive evidence that these people _drank_ the germ of the disease and _did not breathe it_. "It is claimed that after a wet season there is more malaria in the air, and that hence people are more subject to disease. I have investigated this, and my observations, extended over a number of years, have convinced me that the water in the wells is simply raised to a newer stratum, one not thoroughly washed, as it were, and that people drink the germ of disease, and do not breathe it. "My conclusions are, therefore, that irrigation will tend to bring on malarial disorders, as it raises the water in wells to a newer stratum of earth, but no further. When we irrigate so as to produce this effect we must _go down_ after pure drinking water, or bring it to our houses in pipes. The effect of disorders thus brought about is easily remedied. "I do not wish to be understood as maintaining that there may be no such thing as poison in the atmosphere. In some localities, where the air is not in motion every day, as it is here, the air, like standing water, may become stagnant. I know of some hotels in this valley totally void of drainage, and where the accumulated filth of a quarter of a century stands in the yards in cess-pools. In some countries this would kill ninety out of a hundred people who would stop in them a week, but here we feel no inconvenience from it, except in so far that the water may become impregnated. Air in motion, like water in motion, purifies itself, and hence I have come to the rejection of the theory of malaria in the air."