This book is based partly on a. lecture course given at the University
of Tri- este, but mostly on my own research experience in the field of
galactic chemical evolution. The subject of galactic chemical evolution
was started and developed by Beat- rice Tinsley in the seventies and now
is a flourishing subject. This book is dedi- cated to the chemical
evolution of our Galaxy and aims at giving an up-to-date review of what
we have learned since Tinsley's pioneering efforts. At the time of
writing, in fact, books of this kind were not available with the
exception of the excellent book by Bernard Pagel on "Nucleosynthesis and
Chemical Evolution of Galaxies" (Cambridge University Press, 1997), and
the subject of galactic chem- ical evolution has appeared only as short
chapters in books devoted to other subjects. Therefore, I felt that a
book of this kind could be useful. The book summarizes the observational
facts which allow us to reconstruct the chemical history of our Galaxy,
in particular the abundances in stars and in- terstellar medium; in the
last decade, a great deal of observational work, mostly abundance
determinations in stars in the solar vicinity, has shed light on the
pro- duction and distribution of chemical elements. Even more recently
more abun- dance data have accumulated for external galaxies at both low
and high redshift, thus providing precious information on the chemical
evolution of different types of galaxies and on the early stages of
galaxy evolution.