Samuel G. Soal was described by Rhine as one of his harshest critics, running many similar experiments with wholly negative results. However, from around 1940 he ran forced-choice ESP experiments in which a subject attempted to identify which of five animal pictures a subject in another room was looking at. Their performance on this task was at chance, but when the scores were matched with the card that came "after" the target card, three of the thirteen subjects showed a very high hit rate. Rhine now described Soal's work as "a milestone in the field". However analyses of Soal's findings, conducted several years later, concluded that the positive results were more likely the result of deliberate fraud. The controversy continued for many years more. In 1978 the statistician and paragnost Betty Markwick, while seeking to vindicate Soal, discovered that he had tampered with his data. The untainted experimental results showed no evidence of precognition.