Great caution should always be observed in using this powerful drug, as it will sometimes act so energetically as to _burst the womb_; or expel the child so suddenly as to lacerate the perineum and other parts. The contractions produced by it are different from the natural ones, being almost constant, without any interval, and gradually increasing in force. They usually come on in about ten or fifteen minutes after the last dose, and continue about an hour and a half. Some practitioners depend almost altogether on the ergot, in every protracted case, and even use it to bring on _premature labor_, when that is required. Thus M. P. Dubois was once called to a dwarf, whom he delivered with instruments, the first time, but with great difficulty and risk. The next time she became pregnant he determined to bring on premature labor, and accordingly he administered ergot, when she was about _eight months_ gone. This brought on natural labor, and she was delivered without difficulty. M. Chailly says he believes it will bring on uterine contraction at any time, and that he has never known it to fail. I consider however that there is always more or less risk in its use, and I should certainly prefer any of the other means, particularly _Galvanism_. It is of the first importance however to be certain, before using _any forcing means whatever_, that there is no _physical impediment_. If the pelvis should be deformed or small, if the child's head should be unusually large, or dropsical, or if the soft parts of the mother should be undilated and rigid, the most serious consequences must ensue from violent uterine contractions. In like manner if the presentation be unfavorable, particularly if it be one of the trunk, the danger is equally great. In every case the passage of the child must be _physically possible_, before it is attempted to force it away. A neglect of this rule has frequently led to fatal results. The ergot has been given and the uterus forced to contract, while the pelvis was too small for the child to pass through; and the consequence has been _rupture of the uterus_, or complete exhaustion, with death to both mother and infant. In other cases the delivery has resulted so suddenly, from the violence of the expulsive efforts, that the vagina and perineum have been lacerated in the most shocking manner. The ergot is also especially dangerous to very nervous women, or to those who are disposed to congestion, apoplexy, or inflammation.