LOS ANGELES — Swiss scientist Albert Hofmann may have invented LSD, and Timothy Leary was clearly its most prominent frontman.

But it was a self-taught chemist and obscure-by-choice figure named Nicholas Sand who was the true wizard behind the curtain, the man who launched tens of millions of acid trips across generations by producing the most pure, highest-quality acid ever consumed.

Sand, who with fellow chemist Tim Scully created the legendary version of LSD known as “Orange Sunshine” that first hit the streets of San Francisco in 1967, died April 24 at his home in the Northern California community of Lagunitas.

He was 75 and had spoken just the day before at a “Psychedelic Science Conference” in Oakland where the film “The Sunshine Makers” was screened.

“Nick had commented to some friends afterward that it was like the best weekend of his life, and then he went home and died in his sleep, so I guess he went out on top,” said longtime friend Lorenzo Hagerty, host of the internet program “The Psychedelic Podcast.”

Born in Brooklyn on May 10, 1941, Sand was the son of prominent chemist Clarence Hiskey, who had worked on the top-secret Manhattan Project to develop the atomic bomb until authorities caught him spying for the Soviet Union. After Hiskey’s wife, Marcia, divorced him she restored her maiden name and gave it to her son.

Nicholas Francis Sand would earn a degree in anthropology and sociology from Brooklyn College in 1966, but by then he had already begun to chart a different path.

Two years before, when LSD was still legal, the longtime devotee of yoga had sat naked in the lotus position in front of a roaring fire at a farmhouse in upstate New York and taken his first hit of LSD.

“I was floating in this immense black space,” he would recall years later. “I said, ‘What am I doing here?’ And suddenly a voice came through my body, and it said, ‘Your job on this planet is to make psychedelics and turn on the world.’

“If we could turn on everyone in the world,” he added, “then maybe we’d have a new world of peace and love.”

A year later, Sand’s reputation as a drug chemist had spread to San Francisco, where another self-taught chemist, Owsley Stanley, was cranking out millions of doses of LSD.

Stanley introduced Sand to yet another self-taught chemist, Tim Scully, and they began producing Orange Sunshine doses. They had produced about four million when the government, which had outlawed LSD in 1966, busted them.

Sentenced to prison, Sand vanished into Canada, living on the run for the next 20 years while cranking out LSD hits by the millions. When authorities finally raided his lab in 1996, he boasted that they seized enough doses to turn on every Canadian citizen twice.

“He was dedicated to the proposal that psychedelics, when used properly, could really change the world,” his friend, Hagerty, told The Associated Press on Tuesday. “He really believed in what he was doing, and of course he paid the price.”

Sand is survived by his partner, Gina “Usha” Raetze.