The science of psi, then, was based in a willingness to shift?
"Eight Keys to Eden"
Mark Irvin Clifton
Subconscious psi, possibly, but a spark.
"Border, Breed Nor Birth"
Dallas McCord Reynolds
His system injected the fuel into the cylinder head with a blast of air supplied by a special air reservoir at a pressure of 1000 psi or more.
"The First Airplane Diesel Engine: Packard Model DR-980 of 1928"
Robert B. Meyer