Jay McLean, who as a second year medical student isolated an anticoagulant substance which was later named heparin, seemed to have expended his intellectual energies early in his professional days. He encountered and overcame substantial obstacles in preparing for a medical career, but his scientific maturation was not commensurate with his initial and only success in laboratory investigation.
McLean was born in San Francisco into a physician's family.1 His father died four years later; the earthquake and fire of 1906 destroyed the family home and ruined his stepfather's business. Lacking parental support, he turned to interim nonprofessional jobs while completing his basic education. After graduating from Lowell High School in San Francisco, McLean finished two years of undergraduate work at the Berkeley campus of the University of California. He then stopped school and worked for 15 months in a Mojave Desert gold mine. Returning to Berkeley for a third