> >One of the fascinations of dialling for me is the still-unexpected richness >of the field, going beyond, as it does, the simple matter of an alternative >to a clock. On this latter point, a clock is used for telling the time but >also for measuring elapsed time - as an egg-timer does. Does anyone know of >a gnomonic method or device to measure short periods of time (say, four and >a half minutes) separately from telling the time ? > >
I think the most accurate method for telling short time, is a Meridian Line or similar instrument. If the Gnomon is very hight (say many meters) the spot light on the floor goes slow, and you can mesure minutes and seconds. In San Petronio church of Bologna, the Gnomon is 27,07 meters. In the Winter Solstice the spot light has a velocity of 0,314 meters in a minut. Ciao Giovanni Paltrinieri Gnomonista in Bologna Italy
