From what I see online, it looks like Peruvian Torch and San Pedro are constructed as follows, going from the surface to the center:
1. semi-clear, flaky wax layer (the cuticle?)
2. green, waxy skin (the epidermis?)
3. light green tissue (the primary phloem?)
4. whitish tissue (the secondary phloem?)
5. a thin, round layer of tough fibers (the vascular cambium?)
6. nearly white "woody" tissue (the secondary and primary xylem?)
They say 37.5 grams of dried Peruvian Torch yields a 300 mg dose of mescaline (as a rough ballpark figure). But apparently that applies to the cactus as a whole, and the alkaloids are actually almost entirely in the light green flesh. So how many grams of dried light green flesh alone do you need for a 300 mg dose? And for that matter, am I right that there's no mescaline in the outer whitish fibrous material (the part I'm calling "layer 4", and which I'm guessing is the secondary phloem)?
Ingesting mescaline-containing cactus is illegal in the jurisdiction where the SPF server resides, and we do not encourage our readers to engage in illegal activity. Maybe bluelight.ru can answer your question.