Transformer Oil

Just wanted to say thanks to Richard Quick, Zap Mark, Scott Meyers
and Ed Sonderman for your help on my questions for a new coil.	I
expect it is going to take me many months to construct this because
my time to work on it is limited.

I downloaded the COILBLD file and found it extremely helpful.  My
plans are to build a 6" dia. secondary 24" long with #22 magnet wire.
First, to clarify the transformer that I have - I had several similar
questions - It is 12KV -at- .12A sunk in oil.  I am pretty sure it does not
have any internal current limiting.

Can I use a variac to current limit this transformer?  I will be using a
another variac to vary the input voltage.

I am also trying to determine the kind of oil inside this thing.  Does
anyone know how to tell?  The transformer is in a large metal casing
and is from around 1948 or so.	It came out of a source unit for a
spectrograph. (Wondering if it contains PCB's)

It turns out that I have 2 of these things.  I am planning on paralleling
them.  This means I will have close to 3KW available.  Is that power
level still appropriate for a 6" diameter secondary?