1. The paper first discusses the determination of the mechanical stability of latex when stirred in a Hamilton-Beach mixer. Data are given on the stability of fresh latex, ammoniated latex, and concentrated latex. Particular attention is called to the increase in stability of ammoniated latex which takes place during storage, a phenomenon which is probably attributable to the formation of soap and accompanying increase in the charge of the latex particles. Soap added to latex increases considerably its stability and creaming capacity. 2. Fresh latex, stirred rapidly in a Hamilton-Beach mixer, undergoes microflocculation. The rapidly stirred latex coagulates entirely when it is allowed to stand quietly within a period of time which becomes shorter to the extent that stirring causes the mixture to approach more closely the point of actual coagulation in the mixer. This offers the possibility of coagulating fresh latex completely without the use of chemicals, but the method could be applied on a factory scale only with extreme difficulty. 3. When ammoniated latex is stirred rapidly for a time shorter than required for coagulation to become appreciable, microflocculation results. If, after having been stirred, such latex stands quietly, partial coagulation results. In this case the quantity of coagulum is greater, and the time for it to form is shorter, the more closely the mixing period approaches the coagulation point in the mixer.

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