William "Chops" Westfield <westfw <at> mac.com> writes:
=20
> You can find devices that operate on the same effects.  "Tuning fork
gyroscope" and "Tuning fork
> accelerometer" are both real things.
>=20
FWIW: there are devices that measure a change of resonant frequency of a
crystal in response to weight placed on the free end of the crystal.  It is
possible to directly measure atatchment of a single viral particle (~ 70-90
nm diameter), and, I believe, it is also possible to measure mass of a
single protein molecule ( MW ~100,000 Da, or ~1.6 x 10 ^ -19 g).  All this
is in the "normal" gravity field.  =20

Without knowing the details of the crystal configuration, the effect seems
feasible enough. =20

Sergey


--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.