 Byne was convinced that butyric acid was present together with calcium acetate in the affected shells , although he never really described the methods he used in the so @-@ called " extensive chemical tests " he claimed to have applied to these specimens . Among other conclusions , he assumed that the butyric acid originated from bacterial activity . He also concluded that the decaying effect ' travelled from shell to shell and drawer to drawer ' , and thus the condition came to be called a " disease " . 
