sentences:  The opponents and supporters of chloroform were mainly at odds with the question of whether the complications were solely due to respiratory disturbance or whether chloroform had a specific effect on the heart.Between 1864 and 1910 numerous commissions in Britain studied chloroform, but failed to come to any clear conclusions.It was only in 1911 that Levy proved in experiments with animals that chloroform can cause cardiac fibrillation.