Toscanini observed in terms of career and musicianship and influence gives the more than casual listener an interpretative reference. Mr. Marsh points to clarity and accuracy and brilliance as Toscanini's greatest assets in conducting, his tendency to polish to a cool finish, his weakness. His influence came in killing the lush hangover from the 19th Century, showing the clarity possible in orchestral performance, his attitude as a servant to music. There are references to personality but there is little private material here. The discography is the sanctioned one with commentary on technical and interpretative elements and period differences; the repertory is listed and noted as limited by habit as well as inclination or intuition. There is comparison with other leading conductors and an honest evaluation of Toscanini's brilliant and special gift.