Provides a very useful insight and background to current variable star work. Liberally sprinkled with references to solar and stellar spectroscopy and very readable. This perennial work first published in 1910 must now be close to a 20th edition. Contains starcharts to mag 6 covering the whole sky and invaluable to the amateur planning an evening's observation. Text of over 113 pages includes the basics of spectroscopy.
Most stellar objects have their spectral class listed.
In valuable reference for the keen observer.