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MATERIALS FOR MOVING-GLOBULE LAMPS
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From Charles R. Patton, Feb 1999:


I believe I ran across some references on your site while I was looking
for the Kalliroscope fluid.  People seem to be guessing at the liquid
compositions.  You might be interested in the following. The original
patent by David George Smith of England is 3,387,396 for a "Display
Device".  The listed two fluids are water and a "solidified globule of
mineral oil, paraffin and a dye as well as paraffin wax or petroleum jell,
preferably Ondina 17 with a light paraffin, carbon tetrachoride, a dye and
the paraffin wax or petroleum jelly."  The patent is very short, only 3
pages total.  But it includes all the aspects including the reason for the
wire spring in the bottom.  [Go to Delphion and search for US03387396 ]


*********************************************************************
From Sean L, TAP-L Listserv, 7/95

> Does anyone know what is in a liquid-globule lamp?  Does anyone know how
> to make those wave things that I always see (some blue fluid and yellow
> or clear fluid between two sheets of plexi.)? 

The stuff inside is (I believe) a trade secret - imagine that.  A pretty
good substitute can be found in this: 

        Benzyl alcohol (probably around 150 - 250 ml)
        4.8% salt water solution (48 g per liter)

Benzyl alcohol has a specific gravity of 1.043 g/cc and the brine solution
has a s.g. of 1.032 g/cc.  When heated, the benzyl alcohol expands enough
to become less dense than the brine.  Once it cools off, it becomes heavier
(denser) and it falls.  The cycle hopefully repeats.  I've built several of
these with students, using a 40 - 60 W light bulb as a heat source.  The
bulb is in a fixture in a can (small coffee can or such) close to the
bottom of the vessel for the mixture.  To get the color, find an
oil-soluble marker (Magic Marker?) and break it open.  Carefully remove the
felt ink-soaked thing (technical talk; sorry) and place it in a small bowl
with the benzyl alcohol.  The longer you leave it in, the darker it will
become.  A couple of minutes should do the trick.  The darker it is,
however, the more it will tend to bleed into the brine solution.  I've
heard from my students that Sharpies bleed too much, so you may want to
avoid them as an ink source.

Also, benzyl alcohol is a bit expensive:  about $40 per liter (enough for
6-7 lamps).  Other liquids work too, but may be more dangerous or costly: 

        cinnamyl alcohol
        diethyl phthalate
        ethyl salicylate
        nitrobenzine

Experimentation is the key here.  Oh, these do work very well if you have
a good container.  I've not had a chance to try this mixture in an old
lamp assembly, though I can't imagine why it wouldn't work well. 

By the way, more detailed ideas on this can be found in an article in a
back issue of Popular Electronics (March of 1992?  93?  I'm not sure) by
Ralph Hubscher.  It describes pretty much what I just have, but with
better graphics and grammar:-) 


As for the wave tank, here's a sure fire technique:  baby oil and water,
and food coloring.  Find a good bottle and an old VW wiper motor (JerryCo
{American Science and Surplus} or JC Whitney) for your own wave machine.

Hope this helps.  Sorry for the delay in responding but I've just moved
recently and only now have gotten around to checking my e-mail.  Yeesh,
where are my priorities?  175 messages!!!

Bye now,

Sean

***********************************************************
From: stormoen@sparc.isl.net (Stormoen MD)
Newsgroups: alt.drugs
Subject: Lamp Plans Here.
Date: 13 Jan 1995 08:08:15 GMT
Message-ID: <3f5cdf$jun@news.isl.net>

I've had SEVERAL requests for the plans, so here they are.

Sorry, I guess I lost the name of the guy who gave 'em to me.
(I recieved two versions, and I liked this one best).

WARNING!!  This electronic document deals with and involves subject matter
and the use of materials and substances that may be hazardous to health
and life.  Do not attempt to implement or use the information contained
herein unless you are experienced and skilled with respect to such subject
matter, materials and substances.  The author makes no representations as
for the completeness or the accuracy of the information contained herein
and disclaim any liability for damages or injuries, whether caused by or
arising from the lack of completeness, inaccuracies of the information,
misinterpretation of the directions, misapplication of the information or
otherwise. 

Please note:  The information contained in this electronic document can 
be found in the 1992 Edition of Popular Electronics Electronics Hobbyists 
handbook, published annually by Gernsback Publications Inc, USA.


Inside the lamp are two immiscible fluids.  If it is assumed that fluid
1 is water, then fluid 2 must be: 

	1) insoluble in water;
	2) heavier than water;
	3) non-flammable (for safety);
	4) non-reactive with water or air;
	5) more viscous than water;
	6) reasonably priced.

Furthermore, fluid 2 must not be:

	1) very poisonous (for safety);
	2) chlorinated;
	3) emulsifiable in water (for rapid separation).

In addition, fluid 2 must have a greater coefficient of expansion than 
water.  Check a Perry's handbook of Chemical Engineering, and the above 
list eliminates quite a few possibilities.

Here is a list of possible chemicals to use:

	1) benzyl alcohol (sp.g. 1.043, bp 204.7 deg. C, sl. soluble);
	2) cinnamyl alcohol (sp. g. 1.04, bp 257.5 deg. C, sl. soluble);
	3) diethyl phthalate (sp. g. 1.121, bp 298 deg. C, insoluble);
	4) ethyl salicylate (sp. g. 113, bp 233 deg. C, insoluble).

If desired, use a suitable red oil-soluble dye to color fluid 2.  A 
permanent felt-tip pen is a possible source.  Break open the pen and put 
the felt in a beaker with fluid 2.

It is recommended to use benzyl alcohol as fluid 2.  (Caution!! Do not 
come into contact with benzyl alcohol either by ingestion, skin, or
inhalation.)  In addition to water, the following items will be necessary:

	1) sodium chloride (table salt);
	2) a clear glass bottle, about 10 inches (25.4 cm) high;
	3) a 40 watt light bulb and ceramic light fixture;
	4) a 1 pint (473 ml) tin can or larger;
	5) plywood;
	6) 1/4 inch (0.635 cm) thick foam-rubber;
	7) AC plug with 16 gauge lamp wire;
	8) hardware;
	9) light dimmer (optional);
	10) small fan (optional).

The performance of the lamp will depend on the quality of the water
used.  A few experiments must be conducted to determine how much sodium
chloride is necessary to increase the water's specific gravity.  Try a 5%
salt concentration first (50 g of salt to 1 liter of water).  Pour the
red-dyed benzyl alcohol mixture in a Pyrex beaker.  Add an equal or
greater amount of water and heat slowly on a hot plate.  If the benzyl
alcohol floats to the top and stays there, decrease the salt
concentration.  If it stays at the bottom, add more salt. 

Construct the lamp by fastening the ceramic lamp fixture to a 5 inch (12.7
cm) diameter piece of plywood.  Attach the lamp wire to the fixture. 
Screw in the 40 watt bulb.  Cut one end off the tin can, remove its
contents, and clean thoroughly.  Drill a hole in the tin can for the wire
to go through.  Invert the can over the bulb (open end down) and affix to
the plywood with epoxy.  Cut a round gasket from the foam-rubber and fit
it into the top lip of the can. 

Fill the bottle partially with brine, add about 150 ml of benzyl alcohol, 
then fill up the bottle with brine.  Leave about 1 inch (2.54 cm) of 
airspace on top for expansion.  Bubble size will be influenced by amount 
of air space.  Tightly cap the bottle and place on gasket.

The light dimmer is used to control the amount of heat in the bottle.  It 
is helpful if the bottle is too short and the 40 watt bulb makes the 
benzyl alcohol accumulate at the top.

The fan can also be used to cool the top of the bottle and help the benzyl
alcohol to sink to the bottom. 

If desired, add a trace of an antioxidant such as BHA or BHT to the brine
to add color and contrast.

Enjoy and good luck.





*********************************************************************
BILLB:

Some theorizing:  The wax material smells like gasoline.  That seems
unsafe, but could it perhaps be a mixture of paraffin wax thinned by
gasoline? By itself this wouldn't sink in water, but by varying the
amounts it might be possible to adjust the viscosity and melting point. 
The mixture might not be very flammable if only a small amount of gasoline
is needed.  Use extreme care if you experiment with flammable materials! 
  
Another clue:  after a few years a Lamp fails because the wax
separates into two masses, one which floats and one which sinks.  This
suggests that one ingredient may be a finely powdered solid.  Over time
this solid settles to the bottom of the wax blob, and eventually the
lower part of blob becomes too dense to float when heated.  The
heavy powder would need to be very fine, and should be dense enough to
sink the wax, but not so dense that it settles within the blob quickly.
Could it be something as simple as talc?  Or maybe it's very fine powdered
silica.  This powder would also make the wax appear translucent, while
other mixtures usually result in a blob that is as transparent as glass.

- Bill Beaty


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