1. Taking special care to avoid raising dust. It is to the interest of everyone to see that ventilating arrangements are in order for carrying dust away at the point where it is produced. Any little cloud constantly made at work is sure, if breathed, to set up lead poisoning. Where lead colours are used wet, danger arises from the splashing of the material and its subsequent drying into dust. 2. Paying scrupulous attention to cleanliness of the hands, face, teeth, and clothing. The hands and nails should always be cleaned with soap and nail-brush before food is eaten, and it is a wise practice also to wash out the mouth. The teeth should be brushed at least once a day, preferably before the evening meal. 3. Never commencing work on an empty stomach. Food containing fat, such as bacon and milk, is suitable. Overall suits, if worn, should never be shaken to rid them of dust. They require washing at least once a week. Aperient medicine, such as Epsom salts (one or two teaspoonfuls in water), can be taken once or twice a week with advantage by lead-workers. Experience shows that the habits and home life of the workers influence their liability to lead poisoning. Intemperate persons are the first to fall victims. Those who begin work on an empty stomach incur additional risk by so doing. Carefulness while at work, and cleanliness, offer the best means of escaping attacks of lead poisoning. Those who work in lead should keep in mind every hour of every working day the importance of not breathing lead dust and not carrying lead to the mouth in any way. Medical advice should at once be obtained if signs of lead poisoning present themselves. REFERENCES. [1] GEORGE REID: Memorandum on Mess-room Accommodation: Appendix XXV. of the Potteries Committee’s Report, vol. ii., 1910. Cd. 5278. [2] TH. SOMMERFELD: Die Bekämpfung der Bleigefahr, edited by Leymann, p. 76. CHAPTER XV DESCRIPTION OF PROCESSES Lead smelting--Red and orange lead and litharge--Letterpress printing--File-cutting--File-hardening--Tinning of metals--Plumbing and soldering--Brass. =Lead Smelting and Silver Refining.=--Lead poisoning very rarely occurs in lead mining in Europe, as galena (sulphide of lead), the principal ore in which the metal is found, is insoluble. Galena always, and other lead ores very often, contain a small proportion of silver, ranging from 0·001 to 1 per cent., and at times traces of gold. Owing to the great affinity of lead for silver, lead smelting is necessarily a process preliminary to the extraction of silver and gold from it[1].