After the initial work on installing the air bleed in the cooling circuit, the flow rate in head 3 was lower
than it was before.  There is no reason why the air bleed should affect things.  All the other heads are the
same as previously.  I lifted the lid off the oscillator and looked at the turbine sensor.  Nothing unusual
was seen.  I tapped the flow sensor to see if it might dislodge anything stuck inside but the flow rate did
not change.

    The reduced output power of the laser is real.  I checked the alignment of the monitoring photodiode
that is located near the diagnostic breadboard and it appeared more or less okay.

    I also checked the iris underneath the IO periscope.  The beam appeared to be off there too.  Unfortunately
there are no other irises earlier in the beam bath, so it not easy to tell where exactly the beam may be off
centre.