The Silver Wand 173
abnormal texture in response to ions of dissolved silver, which migrated
only about a hundredth of a millimeter. There were no other effects in
the control or negative-current chambers.
Around the positive poles, however, this region was succeeded by an
area of great activity for a distance of 5 millimeters on all sides. While
doing their job of holding things together, fibroblasts have a charac-
teristic spiky shape, with long sticky branches extending in all direc-
tions. In this region where silver ions had been driven by the current,
many of the cells had changed to a static, globular form in which
mitosis didn't occur. They seemed to be in suspended animation, float-
ing freely instead of adhering to other cells or the sides of the dishes as
usual. Mixed among them were many featureless cells with enlarged
nuclei, the end products of dedifferentiation. More and more of the
rounded fibroblasts turned into fully despecialized cells as the test pro-
gressed. Beyond the 5-millimeter line was a border zone with partial
changes, followed by a realm of normal, spiky fibroblasts. Dedifferenti-
ated cells normally divide rapidly, but these didn't, perhaps because
they were sitting in a plastic dish far removed from the normal stimuli
of an animal's body. Within a day after the current was turned off, the
cells clumped together into bits of pseudotissue that looked like the
young "bone marrow" we'd seen in the exudate. After two weeks they'd
all reverted back to mature fibroblasts, presumably because regular re-
placement of the nutrient medium had by then washed out all the silver
POSITIVE SILVER DEDIDIFFERENTIATES CONNECTIVE TISSUE CELLS