May 1, 1961

MEMO TO FILE

Call to Jerry Stewart at JPL (tried to get George Hobby as well, but
he was out).

JPL would like to keep the mechanical aspects of the multivators
an in-house project and we will go ahead on this as a collaborative experiment.
| briefed him on the current status of phosphatase assay In particular the
very promising numbers that Elliot Packer has been getting where he can
readily characterize the phosphatase from one ml of soll. We discussed
briefly an AC/DC system for getting two wavelength measurements and this
can be kicked around further. Fluorescent measurements are also in the
picture for they are on.

He will think a Ilttle more about the possible use of a windmi!]
arrangement, In place of the parachute, to furnish power as well as
breaking during the atmospheric descent. He thinks the problem of providing
for the lubrication may be a difficult one.

We also discussed several schemes of video photography which would
depend on the capacity to store rather more pictures In the capsule than
are actually sent to the bus. However, the stringent welght Ilimitations now
make it unlikely that there will be any storage at all. The two storage
schemes | had In moad were |) for the selection of fields on the basis
of maximum detail that Is high frequency components and two tracking of moving
objects, particularly after the landing. However, if the Mariner program
Is expended there may egain be room for these refinements as well as for
some of the other things that are missing, e.g., en'Independent check on
the altitude.

JPL has put one microscope photograph back into the proposal since
thls can be done by having a single lens as an alternative bjective In the
photographic system. This would Just look at whatever it fell on.