breather.

Now all three doctors began work on the specimens. Cultures were
inoculated with specimens from respiratory tract, blood and tissue taken
from both sick and well. Half a dozen fatal cases were brought to the
ship under specially controlled conditions for autopsy examination, to
reveal both the normal anatomical characteristics of this strange race
of people and the damage the disease was doing. Down on the surface
Tiger had already inoculated a dozen of the healthy ones with various
radioactive isotopes to help outline the normal metabolism and
biochemistry of the people. After a short sleep period on the _Lancet_,
he went back down alone to follow up on these, leaving Dal and Jack to
carry on the survey work in the ship's lab.

It was a gargantuan task that faced them. They knew that in any race of
creatures they could not hope to recognize the abnormal unless they knew
what the normal was. That was the sole reason for the extensive
biomedical surveys that were done on new contract planets. Under normal
conditions, a survey crew with specialists in physiology, biochemistry,
anatomy, radiology, pharmacology and pathology might spend months or
even years on a new planet gathering base-line information. But here
there was neither time nor facilities for such a study. Even in the
twenty-four hours since the patrol ship arrived, the number of dead had
increased alarmingly.

Alone on the ship, Dal and Jack found themselves working as a well
organized team. There was no time here for argument or duplicated
efforts; everything the two doctors did was closely co-ordinated. Jack
seemed to have forgotten his previous antagonism completely. There was a
crisis here, and more work than three men could possibly do in the time