It was an oaken tub with metal rods on the two long sides, from
which depended prismatic carbon rods. Kennedy examined it closely.

"This is what we call a hydro-electric bath," Josephson explained.
"Those rods on the sides are the electrodes. You see there are no
metal parts in the tub itself. The rods are attached by wiring to
a wall switch out here."

He pointed to the next room. Kennedy examined the switch with
care.

"From it," went on Josephson, "wires lead to an accumulator
battery of perhaps thirty volts. It uses very little current. Dr.
Gunther tested it and found it all right."

Craig leaned over the bath, and from the carbon electrodes scraped
off a white powder in minute crystals.

"Ordinarily," Josephson pursued, "lead is eliminated by the skin
and kidneys. But now, as you know, it is being helped along by
electrolysis. I talked to Dr. Gunther about it. It is his opinion
that it is probably eliminated as a chloride from the tissues of
the body to the electrodes in the bath in which the patient is
wholly or partly immersed. On the positive electrodes we get the
peroxide. On the negative there is a spongy metallic form of lead.
But it is only a small amount."

"The body has been removed?" asked Craig.