The book "Cannabis Chassidis: The Ancient and Emerging Torah of Drugs", was published in 2009 by the author Yoseph Lebi, and just recently was posted on a network by the author himself for public reading.
The book in general is an insightful exploration of what Jewish source think about Drugs and chemical experimentation.
In this book Leib confirms his own thoughts and ideas about usefulness of cannabis with the quotes from Jewish texts and sages. Like "I have given you every plant yielding seed which is upon the earth". He retells Rabbi Nahman of Bratslav's admonition that each blade of grass "has it's own song, and it's ownpower to heal , and it's own angel, telling it to grow", including marijuana, that according to Leib, also "has it's own special power to heal".
Not the first year when the Rebbis have debates about wether marijuana is kosher, and if you can use it in Pesach. And Israel party "Ale is Bright" have been fighting for the light drugs legalization for a long time already.
Still try to read this book, you wil find lots of new interesting thoughts about how cannabis effects people minds, souls and bodies.