Charles Mallory Hatfield (July 15, 1875 – January 12, 1958) was an American "rainmaker".
Hatfield was born in Fort Scott, Kansas on July 15, 1875. His family moved to Southern California in the 1880s. As an adult, he became a salesman for the New Home Sewing Machine Company. In 1904, he moved to Glendale, California.
In his free time Hatfield read about "pluviculture" and began to develop his own methods for producing rain. By 1902 he had created a secret mixture of 23 chemicals in large galvanized evaporating tanks that, he claimed, attracted rain. Hatfield called himself a "moisture accelerator".
In 1904, promoter Fred Binney began a public relations campaign for Hatfield. A number of Los Angeles ranchers saw his ads in newspapers and promised Hatfield $50 to produce rain. In February, Hatfield and his brother Paul built an evaporating tower at La Crescenta where Hatfield stood and released his mixture into the air. Hatfield's apparent attempt was successful, so the ranchers paid him $100. Contemporary Weather Bureau reports stated that the rain had been a small part of a storm that was already coming but Hatfield's supporters disregarded this.
He began to receive more job offers. He promised Los Angeles 18 inches (46 cm) of rain, apparently succeeded, and collected a fee of $1000. For this effort, Hatfield had built his tower on the grounds of the Esperanza Sanitarium in Altadena, near Rubio Canyon.
In 1906 Hatfield was invited to the Yukon Territory, where he agreed to create rain for the water-dependent mines of the Klondike Goldfields. The Klondike contract was for $10,000, but after unsuccessful efforts, Hatfield slipped away, collecting only $1,100 for his expenses. This failure did not deter his supporters.
In 1915 the San Diego city council, pressured by the San Diego Wide Awake Improvement Club, approached Hatfield to produce rain to fill the Morena Dam reservoir. Hatfield offered to produce rain for free, then charge $1,000 per inch ($393.7 per centimetre) for between forty and fifty inches (1.02 to 1.27 m) and free again over fifty inches (1.27 m). The council voted four to one for a $10,000 fee, payable when the reservoir was filled. A formal agreement was never drawn up, though Hatfield continued based on verbal understanding. Hatfield, with his brother, built a tower beside Lake Morena and was ready early in the New Year.