This podcast is from the current edition of the Rosicrucian Digest, and it features two meditations used by the alchemists in the Middle Ages and Renaissance. You can download the print article (pdf) from:
https://77a5ba0729622e5e80ac-c808e8d6f5a119605d9b0e3ef89bbea9.ssl.cf5.rackcdn.com/Searching_for_the_Cosmic_Quintessence.pdf