On the non existent Vitamin A. The first failed (Japanese) 'isolation' attempt (1924). Note: no definite chemical formula was discovered and a dying rat was the only forced witness. Source: https://www.science.org/doi/10.1126/science.60.1550.x.s ![[Pasted image 20260110184511.png]] The 2nd failed 'isolation' attempt (1937) where the chemical formula was given (by Karrer) even before the isolation experiment. Since Vitamin A was unknown, how could one be sure 60 rats were "depleted of Vitamin A"? Source: https://www.cabidigitallibrary.org/doi/full/10.5555/19371404625 ![[Pasted image 20260110184526.png]]