Abstract: A storage rack for video tape cartridges permitting storage of a plurality of cartridges in a close linear array and arranged for ease of individual selection. The rack is preferably constructed of plastic having an open front and internal divider walls sectioning the rack into closely adjacent cartridge compartments. The base of the rack has a rear section maintaining the cartridge normally in a rearwardly tilted position and a front section sloped forwardly so as to allow selection by rotating the cartridge to permit the cartridge bottom to be guided by the front section and at the same time tilted forwardly at its top end thus extending out of the rack.

Abstract: A container for growing anaerobic microorganisms having a cone-shaped dish and matching cone-shaped cover that define between them a prescribed volume. An overflow trough surrounds the dish, and the peripheries of the dish and cover seal together by excess agar medium carrying the organisms squeezed from the volume as the cover is applied to the dish. The colonies of organisms can be viewed either through the dish or cover because each is transparent.

Abstract: A radioimmunoassay plate composed of a tray and a cover. The tray has a plurality of wells having downwardly tapered side walls and coplanar bottom walls. Each bottom wall has a flat central portion and rounded peripheral portion, the peripheral portion merging into the side wall.

Abstract: A pistol-shaped pipetter capable of operation on a full range of pipettes from 0 to 25 ml and which has a pair of vacuum chambers which are activated by trigger-type devices on the pistol grip of the unit. With a small volume pipette the selector valve is placed in one setting wherein only one of the vacuum chambers is directly connected to the pipette. With a larger volume pipette, the selector valve is positioned so as to place both vacuum chambers in communication with it. A rapid discharge of the fluid in the pipette is achieved by trigger actuation while a fine, controlled discharge is achieved by an air bleed valve control.