Telegraph Beater Churn: Nested Knife-Edged Beaters That Whip the Cream

Robbins compared his agitator's work on cream to that "produced by knives upon the whites of eggs, during the process of what is called whipping them up." Z. C. Robbins of St. Louis, Missouri, received US 6,556, dated 26 June 1849 (antedated 1 June 1849, reissued as No. 159), for what he called the Telegraph Churn: a rotating agitator of four series of thin beaters on radial arms, each series of two, three or more slats one within another with narrow spaces between, narrowing inward. Their front edges are bevelled sharp, their rear edges blunt; reversed, "the butter will be collected into the center." This rung works out when the cream would fly off, then prints the beater series and spiders, fits them in a box, and makes butter.