The Temple or Tower of the Winds, has been very justly termed "the most curious existing monument of the practical gnomonics of antiquity.".    From Wordnik.com.  [The International Monthly Magazine, Volume 5, No. 1, January, 1852] Reference

Before clocks were invented, people told the time by sun-dials, and there was a whole science of sun-dials, called gnomonics.    From Wordnik.com.  [The Boy with the U. S. Weather Men] Reference

There he lived for fourteen years, engaged in mathematics and in physical experiments, and publishing his work on gnomonics and perspective.    From Wordnik.com.  [The Catholic Encyclopedia, Volume 9: Laprade-Mass Liturgy] Reference

Holywood), and a dissertation upon the astrolabe; the fourth contains what was up to that time the most detailed and copious discussion of gnomonics, i.e. the art of constructing all possible sun-dials; finally, the fifth contains the best and most fundamental exposition of the reform of the calendar accomplished under Gregory XIII.    From Wordnik.com.  [The Catholic Encyclopedia, Volume 4: Clandestinity-Diocesan Chancery] Reference