Sidney, this is too late for tomorrow, but for future talks, this booklet (47 pages) is hard to beat: Harp Scoring, by Stanley Chaloupka. This late harpist was Principal Harp of the Los Angeles Philharmonic for many years. His booklet was self-published in 1979 and was for sale by Salvi Harps and perhaps elsewhere, for $5.00. Do try to find a copy; you will not regret it!
I see that http://www.harpcenter.com has it for $8.95. This is the Sylvia Woods Harp Center in La Crescenta, California. Perhaps they could express-mail it to you in time for your Feb. 22 talk.
Show why scale glissandos are noisy and don’t project and how we can make them sound better. And how to notate a glissando. Despite how good it sounds on Finale, a 64th note run for three octaves isn’t the best way.