Abstract: The invention is generally accomplished by providing a tabular-grain silver halide emulsion in which at least 50 percent of the total grain projected area is accounted for by tabular grains having a mean diameter of at least 0.6 micrometer and a spacing between at least two parallel twin planes of less than about 0.011 micrometer. In a preferred form, at least 90 percent of the total grain projected area is accounted for by the tabular grains of the invention having a mean diameter of at least 0.6 micrometer and a spacing between at least two parallel twin planes of less than 0.012 micrometer.

Abstract: A photographic silver halide emulsion is disclosed in which the face centered cubic crystal lattice structure of the grains contain at adjacent cation sites metal ions chosen from group VIII, periods 5 and 6. The metal ions are placed at adjacent cation lattice sites by sensitizing the grains with oligomers each containing at least two of the group VIII metal ions.

Abstract: A dumbbell is provided which is collapsible for storage and/or convenient transportability and can be expanded, when required for purposes of exercising, by introduction therein of fluid such as water and sand. The dumbbell comprises a hollow, collapsible container comprising a closed loop of hollow tube having an elliptical or doughnut shape, a hollow handle traversing the gap between the inner walls of the closed loop and a fluid inlet provided with a plug seal. The outer peripheral wall of the closed loop is provided with accordion pleats biased into the closed portion but expandable against the bias under the influence of pressure generated by introduction of fluid into the container. The amount of fluid so introduced is a matter of choice of the user to achieve the desired overall weight of the device. Advantageously the dumbbells are integrally molded from thermoplastic resin.