>Date: Mon, 24 Jan 2000 14:21:40 +1000
>From: jim <jim@proscitech.com.au>
>Subject: FW: oil immersion lens cleaning
>To: "histonet@pathology.swmed.edu" <histonet@pathology.swmed.edu>
>
>	Inverted optics are uncommon. If the recommended highly viscous oil is
used,
>there should be no problem with this running. Again, excess could be just
wiped
>off before application of another drop before the next use.
>

Jim,
	Histonet is not just confined to Pathology labs. Here in the
Davidson/Wolfson/West Medical complex at Glasgow University, buildings that
cover Physiology/PharmacologyBiochemistry and all the variations of these
subjects the upright microscope is the rarity. Inverted microscopes are the
norm. from routine use to experimental setups and confocal. Indeed, I'm
sure if you go into any modern University department covering these
subjects then you'll find inverted microscopes are the major microscope type.
	I agree that there shouldn't be a problem if users wiped the excess
from
the objective after use but human nature doesn't seem to work that way. I
get blue in the face telling users they only need a very small drop but do
they listen, nope, if a wee drop is good then a big drop must be even
better. I use felt washers on the oil objectives of inverted microscopes
and I can assure you they get saturated with oil on a regular basis.
'Wasn't me, must have been *****. I only use a small drop.'
	Immersion oil is bad enough but wait until you get the mixture of
oil and
the vaseline that was used to seal the slide plus the physioplogical salt
solutions that bathe the specimens. After that lot immersion oil is a minor
inconvenience.
Ian.