Here is the link to the page on earthclinic.com that has the excerpt of the book they typed up for us, in the present time, to read:
http://www.earthclinic.com/Remedies/blue_and_sunlight_therapy.html
I am going to be looking for blue gauze like mesh at walmart, the kind that you would make a wedding veil out of and I am also going to experiment with this with my plants, possible with blue gift wrapping tissue tented over some of my more reluctant plants.
By Robyn Fed from Hampton, TN
The blue "gauze mesh" you are looking for is probably called "tulle." You should be able to find it at any fabric store or online.