Francis L. Wellman, The Art of Cross-Examination — Chapter 5 (1903)
“ The whole effect of the testimony of an expert witness may sometimes effectually be destroyed by putting the witness to some unexpected and offhand test at the trial, as to his experience, his ability and discrimination as an expert, so that in case of his failure to meet the test he can be held up to ridicule before the jury, and thus the laughter at his expense will cause the jury to forget anything of weight that he has said against you. ”
