=Sex.=--Women are more susceptible to poisoning by lead than men, and in lead poisoning from drinking water the proportion of women (especially pregnant women) and children attacked is stated to be higher than in men, and one such epidemic is quoted by Oliver where the rise in the number of miscarriages and premature births led to the discovery of the fact that the water-supply was contaminated with lead. The close relationship of lead poisoning to miscarriage has been repeatedly made out, especially by Oliver, in the white lead industry as carried on twenty years ago. Oliver also quotes the effect upon rabbits[9], Glibert upon guinea-pigs[10], and in the experiments of one of us (K. W. G.), referred to on p. 99, all the animals to which lead was given during pregnancy aborted; and, further, with one exception out of eight animals, all died of lead poisoning, not as the result of the abortion, but some time later, although no further administration of lead was made. This confirms the well-known abortifacient effect of diachylon, and there is no doubt that the lead circulating in the maternal blood determines the abortion. Further, observers who have examined the fœtus in such cases have demonstrated the presence of lead in the fœtus itself. Oliver[11] found that eggs painted with lead nitrate did not hatch out, and on opening the eggs the embryos were found to have reached only a limited stage of development, and to have then died, whereas control eggs painted with lime produced live chicks. From what is stated later with regard to the curious action of lead upon the blood, the mechanism of abortion is easily understood; it is probable that placental hæmorrhages are produced, as in other organs of the body. But the effect of lead on the female is not only apparent during pregnancy. A considerable number of women working in lead processes suffer from amenorrhœa, and often from periods of menorrhagia and dysmenorrhœa, which as a rule is the more striking symptom. The effect of lead on the uterine functions, however, only exists so long as the constant intake of the poison is taking place, and many cases are recorded where women, after having had successive abortions while working in lead factories, have ultimately gone through a normal pregnancy and given birth to a living child. This circumstance bears a strong analogy to the similar train of events in syphilis.