I just got a Thermolyne 1300 used furnace and wish to know what I can
use it for.  I looked it up on Google and it says it is a muffle
furnace.  What is a muffle furnace and how is it used?  I make
jewelry, do enameling, fuse dichroic glass.  How can I use it for my
hobbies?

From my days as a chemist, the only thing we used these for was
heating samples so as to be absolutely sure there wasn't any water
absorbed in the sample or crucible when we weighed them.

But then, I wasn't a very good chemist, so there's probably more uses than that.

I don;t think the model 1300 is made anymore, but you can see the
specs for a similar, more recent model at:

http://www.barnsteadthermolyne.com/search_modelnbr.cfm

Your furnace should have a maximum temperature of about 1100 degrees
C.  If your materials melt at lower temperatures than this, it will be
useful for your hobbies.

The link in my previous coment doesn't work.  Here's a better one that
links to the actual operating manual for your furnace:

http://www.barnsteadthermolyne.com/instructions/LT1256X1%20F1300%201400.pdf

I am in the market for a thermal furnace and I am looking for a used
one. I have been told that a thermolyn 1400 would be good for my
application.  Any suggestions on where to look for this item. Perfer
to stay in the US

My original question was to try and determine what a muffle furnace is
used for. Since you want one gccherie-ga, please tell me what they are
used for. Thanks, mysouthstar-ga -

A muffle furnace is a (usually) front-loading box-type oven or kiln
for high-temperature applications (up to 1200°C) such as fusing glass,
creating enamel coatings, etc.

Here is the description of a Muffle Furnace 

Light weight with ceramic fibre wool insulation (instead of Brick
insulation). The outer casing is made of double walled thick P.C.R.C.
sheet, reattached with thick perforated sheet on the bottom portion,
painted with attractive stove enamel. The distinct feature or
perforated sheet is that, it prevents the temperature control unit
from very high heat.

Heating elements are made of KANTHAL "A-1" wire in coil form wound on
the muffle, embedded in high grade refractory cement and backed by
high temperature cerwool insulation, which avoids loss of energy, this
arrangement also assures the most uniform distribution of heat. The
weight & size of Furnace is of one quarter and 30% respectively as
compare to Brick Furnace.

A viewing cap is also provided on the door. Temperature control unit
consists of Energy regulator fitted in front of furnace with two pilot
lamps. The apparatus is complete with one pyrometer, thermocouple,
silver thermal fuse, main lead with power plug to work on 220/230
volts A.C. The energy regulator dial is arbitrarily marked 0-100
position. This marking does not indicate temperature. It indicates
control level i.e. at Position '100' maximum electric is allowed to
flow to Furnace. At Position 'O' minimum electric is allowed to flow
to Furnace.