The contents of a two-dimensional array of vessels are mixed by a vortex created by continuous lateral tumbling of a magnetic stir element against the interior side wall of each vessel. The system includes a drive magnet having oppositely polarized sides, and a carousel including receptacles at different heights and at different positions about the carousel's axis of rotation for receiving a plurality of arrays of vessels. The magnet's vertical physical axis is aligned with the carousel's axis of rotation so that the magnet is disposed to one side of each of the receptacles. The magnet provides magnetic flux lines that rotate horizontally through 360 degrees within the received vessels when the magnet is rotated about its vertical physical axis to thereby cause magnetic stir elements in the vessels to continuously tumble laterally against the interior side wall of the vessel and thereby create the vortexes.

A magnetic stir element includes a stirrer of nonmagnetic material that is configured for stirring the contents of a vessel. The stirrer includes a pair of opposed cavities on opposite sides of the stirrer and a barrier that separates the opposed cavities. Magnetized magnetic material is disposed in the pair of opposed cavities to provide a magnetic flux axis for the stirrer. The magnetic material is so magnetized and disposed in the pair of separated opposed cavities that the magnetized magnetic material disposed in one of the pair of separated opposed cavities is magnetically attracted to the magnetized magnetic material disposed in the other of the pair of separated opposed cavities to thereby hold the magnetized magnetic material within the pair of separated opposed cavities.

A device for providing incremental translation in multiple directions, having a base plate (3), a first plate (1), a second plate (2) and means for translation, such as differentially spaced holes (4,5). When the device includes an optional separate applicator (8) with pins (6) for delivering a specimen to a surface (3d), such as a slide, the device can be used in a method for making microarrays.