You asked where to purchase ferrofluid....well, it is sold by many audio
companies since it is used in certain high end speakers...it is very
expensive for just an ounce or so....I think I paid something like $40
for about 20 drops total....
At one time, I had some instructions for making a 'poor mans ferrofluid',
but I have no idea where that information is....it involved using cooking
oil or singer sewing machine oil and had powdered iron filings mixed
up with it.
The problem is the oil will separate from the filings over time...I would
think ultrasonics could mix it into some kind of emulsion....though a
good mix before any experiments would hold it together....as for
suspension, it wouldn't really be relevant if being excited and
controlled by a magnetic field. In fact, a mayonaisse jar filled with a
clear vegetable type cooking oil with powdered or fine iron on the
bottom, when placed over a speaker magnet would cause the bottom iron to
jump up into 3 space to reflect the pattern....with the oil as the
'gravity reducing' medium. Peter Guy Manners said the images they took
using sand, lycopodium powder, or other fine powders were MAGNIFIED to
show the amazing and very precise geometries that change with
frequency(ies)....
-- Jerry W. Decker / jdecker@keelynet.com http://keelynet.com / "From an Art to a Science" Voice : (214) 324-8741 / FAX : (214) 324-3501 KeelyNet - PO BOX 870716 - Mesquite - Republic of Texas - 75187