Abstract: "By a simple illustration it is pointed out that, conceivably, the real coupled character of the general magnetohydrodynamic equations may lead to much slower instability growth rates, if not stabilization, than predicted from the linearized set of equations."

At the Montreal colloquium Ahmed urged Oliver to make batches of emulsion which would differ only in gelatin concentration. At that meeting Oliver had reported finding a correlation between grain size and silver ion concentration during precipitation, as implied by Perfilov and his Leningrad colleagues. Ahmad felt that one should have more precise knowledge of the relative influence of gelatin concentration of grain sized and their distribution. The incentive is that, in spite of excellent progress in many laboratories and in consistently dependable production from industry (to us, of course, Ilford is most familiar), nuclear emulsions are needed in a wider variety of sensitivities and grain sizes. Available nuclear emulsions have limitations in sensitivity, discriminatory ability, and concentration of hydrogen nuclei. Fine grain size enhances discriminatory ability. An incentive is also in that there is a shortage of literature dealing with the processes involved in the fundamental steps of emulsion production.