The variability will depend on friction between particles and the last particle's physical slide down the glass!
At 05-03-10, you wrote: >Hi > >Even defining when the sand timer is "done" is not a real simple thing. >Waiting for that very last particle to drop may not be the best approach. > >Bob > > >On Mar 5, 2010, at 9:20 AM, Tom Holmes, N8ZM wrote: > >> tvb... >> >> Not to kick sand in your face, but it seems that in order for your automated >> turn-over device to work, as well as to accurately measure the time >> intervals, you would need a means to determine when the sand quits flowing. >> Possibly an accelerometer or microphone, with the added benefit of being >> able to hear the close-in phase noise. >> >> I admire your dedication to monitoring the hour long periods of the sand >> timer so diligently. Truly a time-nut! >> >> Regards, >> >> Tom Holmes, N8ZM >> Tipp City, OH >> EM79xx >> _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.