Ok.........I'll explain.
Back in the late 60's, early 70's, a close circle of friends and I got our acid directly from Owsley Labs. Super pure. It was a pink liquid that came in a little glass vial that we would dip a pin in and lick off. Not very accurate dosing to say the least, but it was unadulterated. I would NEVER drop any of the acid that is available today. Later, when Owsley was no longer available, we would get window pane from a chemist that we knew. There was a period between 1968 to 1977 where I dropped acid almost every other weekend. Must have dropped acid over 200 times.
Also, took synthetic mescaline as well as psyilocybin through shrooms. Must have done those over 50 times. Ate Peyote buttons over 10 different times (only reason I didn't do more is they made me really nauseous). Of course, I only did this on non-working weekends. During the week, did a lot coke (a few grams a week), some speed (pill form), qualudes, seconals, etc etc. I was a real drug garbage disposal. Oh...........smoked a joint on my way from work every day. Did all this for most of a decade.
So here's the deal regarding hallucinations. I never once saw something that wasn't there, nor did anyone else around me. What we did see were things that WERE there, like stationary things such as trees but they would begin to move and morph into some pretty bizarre things like strange faces and such. Kinda like seeing animals in the clouds. I could get lost in tile floors as they began to move much like you would see in a kaleidoscope. Or sidewalks moving in waves like the ocean. Or seeing faces in a textured wall or that same wall moving as if it were breathing.
Hope that kinda explains the hallucinations as I experienced them.
With a strain such as White Widow, I can get the same kind of things going on, but to a MUCH lesser degree, but they happen nonetheless. And even with other strains, the moving images that I can see in GREAT clarity on the back of my eyelids are super clear and vivid. So clear because I'm not really using my eyes to see these things, but rather just my brain creating them. And these are not just swirls of kalidascopic light that I can see if I'm straight, but rather very clear images of very intricate faces, and buildings and plants and flowers as I am very slowly flying over them..............kinda like scuba diving over a really interesting reef. The extreme detail is just amazing. There is no way in hell that I can see these things when I'm not vaped. Now granted, this does not happen all the time, but it does happen and I have to be REALLY vaped to see those eyelid shows.
Anyway, that's my experience of it all.
Could these, in fact, be acid flashbacks brought on by weed. Yup...........sure could. All I can do is relay my experiences.
So when someone tells me that I can't hallucinate on weed, I say..............bullshit.
