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Presents letters to the editor. Facts regarding political coalitions in the U.S.; Information regarding efforts of Republican party of the U.S. to expand itself in the south U.S.; Information regarding a grave charge against an U.S. army personnel.

The distribution of bubbles and the rate of coalescence of bubbles are important factors in the overall behaviour of fluidized beds. A simple model capable of predicting bubble distribution and bubble-size distribution is most desirable. Stages in the development of such a simple model are presented. Early studies examined coalescence and related bubble properties in two-dimensional beds and led to the formulation of a simple computer model for two-dimensional beds. The work was then extended to three-dimensional beds covering the following cases: (i) a single orifice; (ii) a row of orifices in a line and (iii) orifices arranged in a plane. Reasonable agreement with experimental data was obtained for cases (i) and (iii), there being no data available for (ii). The present program is probably adequate for engineering purposes, so far as the prediction of bubble sizes and bubble distribution is concerned, in fluidized beds without internals, although some qualifications are still necessary.

The relative importance of the various physical and chemical processes as they affect the overall rate of mashing has been studied. With sufficiently small particles the physical processes occur rapidly and the chemical reaction is rate-limiting. With large particles, the rate of the chemical reaction is small compared with the slower processes of diffusion. An idealized model of spherical particles, incorporating diffusion with generation and degeneration of the diffusing species can be used to give an approximately quantitative description of the mashing system. The distribution of saccharide end-products appears to be almost independent of particle size, except for particles small enough to pass through 52 BSS mesh and, even then, the distribution varies only during the initial stages of mashing. Under the conditions employed, the contribution of a-amylase in the hydrolysis of starch appears to be highly significant.