Wow, Stan, you were right. The new beamer configuration is >lots< stronger
than the old one with the rectangle magnets.

I measured the old South Pole beamer and the new North Pole beamer several
times in several orientations (to eliminate stray flux from reinforcing bar
which might have been in the concrete below the test area).

	Test #		Beamer		Deflection Dist, inches
	1		old S		11.75
	2		new N		19.25
	3		old S		13.25
	4		new N		19.0
	5		old S		13.25
	6		new N		18.5

	avg		old S		12.75
	avg		new N		18.92

	18.92 / 12.75 = 1.484

	
The magnetic field decays at a rate of 1/d^3. From the ratio, the new beamer 
strength is:

	1.484^3 = 3.27

times the strength of the old beamer. I'm assuming that the polarity didn't
matter (which it wouldn't at the coarseness of my measurement tools).

The old beamer's strength relative to a single 0.38T disc is:

	12.75 / 10.925 = 1.17

	1.17^3 = 1.589

and its rough field strength is:

	1.589 * 0.39T = 0.62T

The new beamer is 3.27 times that, which is:

	3.27 * 0.62 = 2.03T

The two opposite-polarity beamers really like to attract each other, probably
with half a pound of force when they meet. The old beamers' attraction was
barely noticeable. 

Stan, does this field strength make sense? I was using a deviation of the
compass which was five times as great (compared to the ring magnet strength
test recently done), but the ratio should still hold as it is dimensionless.

The first attached photo is the detail of the 3/8" brass tubing in the middle
of the magnets, which holds them in a neat line. The brass screw and its
upside-down finishing washer are in the foreground. The shoulders of the
washer make a nice nesting of the screw central to the opening in the top of
the magnets.

The second photo is of the old beamer, left, and the new beamer, right. I
hadn't done the strength tests on the beamers by the time the photo was taken,
but I did keep the camera a little bit away (about a meter). :) All those
nice, pointy things should be interesting to observe in a 100KV field. 8P

	John