This may be solvable by math... if done correctly with the right numbers....
Cylinder Volume is Diameter x Height x Pi. Via JyARz website the glass cylinder (i believe thats what was measured) is 1.25 inches in diameter and 3 inches in height. That would give V = 3.68155 in^3
so 3.68155^3 is ~49.9
I believe the beads to be about 3mm or 4mm judging by the sizing of the quarters letter (ABOUT a millimeter per letter in "United"). With that you can fit about 3 letters to each bead.
So we will go with 3mm for the sake of the number. 3mm to inches is .11811 inches. Sooo
49.9/.11811 = 422.48. obviously no .48 of a bead can be had to we will say 400 for the sake of it (also because its not full to the brim).
Flaw is the the beads size as 3mm height x 3mm width is 9mm area. But its a guess. And if you want to take a simple way you can count about 20 beads on the surface, and about 20 rows going down, 20*20=400.
Guess is 400