"This day relenting God Hath placed within my hand A wondrous thing; and God Be praised. At His command, Seeking His secret deeds With tears and toiling breath, I find thy cunning seeds, O million-murdering Death. I know this little thing A myriad men will save. O Death, where is thy sting? Thy victory, O Grave? [Poem he wrote following the discovery that the malaria parasite was carried by the amopheline mosquito]"