In the eighteen forties a doctor in Vienna noticed that mothers died far more often in the ward staffed by stud than i the o run b midwives. T students ca straight fr dissections; t midwives d not. H ordered everyone to wash in a chlorine solution, and the deaths fell within a month. His colleagues rejected the finding for twenty years, partly because he could not say what the washing removed and partly because the claim accused them of causing the deaths themselves.

Type only the missing letters. Each box is one letter, and the number of boxes matches the letters that are missing.