_How does lead poisoning show itself?_—The first sign is usually a bluish-grey line on the gums called the blue line, associated with anæmia or pallor. Later symptoms are very varied. Most frequently lead colic comes on, the affected person suffering from violent cramplike pains starting from the navel; the stomach is hard and contracted; very often vomiting and constipation ensue, or, very occasionally, diarrhœa. In some cases paralysis shows itself—generally in those muscles which extend the fingers, usually affecting both arms. In exceptional cases other muscles of the arms and legs are affected. Sometimes lead poisoning manifests itself in violent pains in the joints—generally the knee, more rarely in the shoulder and elbow. In specially severe cases brain trouble supervenes—violent headache, convulsions, unconsciousness or blindness. Finally lead poisoning may set up disease of the kidneys—Bright’s disease and gout. Women suffering from lead poisoning frequently miscarry. Children born alive may, in consequence of lead poisoning, die in their first year. Children fed at the breast are poisoned through the milk. Apart from severe cases complicated with brain trouble, which are often fatal, persons suffering from lead poisoning generally recover if they withdraw from further contact. Recovery takes place after a few weeks, but in severe cases only after months. The most effective preventive measures are cleanliness and temperance. Persons who, without being drunkards, are accustomed to take spirits in quantity are more likely to succumb than the abstemious. Spirits should not be taken during working hours. In regard to cleanliness, file-cutters using lead beds should be especially careful and observe the following rules: 1. Since soiling the hands with lead cannot be entirely avoided, smoking and chewing tobacco during work should be given up. 2. Workers should only take food and drink or leave the works after thoroughly washing the hands with soap—if possible with pumice stone; if drinking during work cannot be wholly given up the edges of the drinking vessels ought not to be touched by the hands. If a file-cutter falls ill in spite of precautions with symptoms pointing to lead poisoning he should, in his own and his family’s interest, at once consult a doctor, telling him that he has been working with a lead bed. Other Industries in which Lead is used