Hi, I've come upon a perplexing question as I've been studying the Study of Orchestration. On P. 30 - 31, Adler distinguishes between unmeasured tremolos and measured effects that kind of sound like tremolos. I can hear the difference in the recorded examples, but am having trouble distinguishing the difference in notation. Both appear to have slashes through the stems of the notes. How do you tell the difference? Is it in context of the passage? Thanks.