 Eijkman thought bacteria caused beriberi), but McCollum's approach differed in that he was seeking the reason for failure in growth.McCollum and Davis's experiments with rat diets led to the discovery that Eijkman's and Grijns' anti-neuritic substance was the same as their water-soluble B (B vitamins) in 1915.The finding is number8 in their list of conclusions, "The water-soluble accessory is not the same one as is furnished by butter fat.