In some factories all new workers are examined by the surgeon before they commence work in dangerous processes. At any rate, a list of such persons should be given to the surgeon at his visit, as naturally the question of personal fitness for employment should be decided at his first examination. Conditions which should lead to rejection are tubercular disease of every kind, idiopathic epilepsy, all forms of mental disease or weakness (hysteria, feeble-mindedness, and neurasthenia), obvious alcoholism, women who are pregnant or who give a history of repeated miscarriages prior to work in lead, persons with marked errors of refraction unless corrected by glasses, kidney disease of all kinds, evidence of previous chronic saturnism, and bad oral sepsis. Special attention will have to be paid to casual labourers, and it should be the aim of the surgeon to discourage this class of labour in lead industries. Work under special rules or regulations requires to be carried out under strict discipline, and this it is extremely difficult to maintain on other than regular workers, who recognize the need for cleanliness and observance of regulations. Other aids to diagnosis cannot be carried out as a matter of routine, but will necessarily be used in particular cases, such as ophthalmoscopic examination of the fundus, electrical reactions of muscles, analysis of the urine, and examination of the blood-pressure. A few words may be added on the significance of the two commonest signs--the blue line and anæmia. It cannot be too strongly insisted on that presence of the Burtonian line on the gums is, as a rule, indicative of lead absorption, and not of lead poisoning. As a danger signal its value is immense, and hardly less so its value in clinching diagnosis in doubtful cases. Whenever the line is seen risk is imminent, and poisoning (not necessarily of the individual in whom it is pronounced) among the workers is inevitable in the absence of adoption of precautions. Unfortunately, careful dental toilet, which the surgeon will necessarily lay stress on, may prevent development, or the practice, when adopted, cause disappearance of the line after the lapse of a few months. Under these circumstances, the merest trace will have all the significance of the fully-developed line in a worker neglectful of care of the teeth. Among new workers a commencing blue line should be strong evidence of the need for dust removal at some point in the process of manufacture. The line, in our experience, is dense in occupations giving rise to fumes or to dust of compounds of lead, but comparatively rare in those handling metallic lead or its alloys, as compositors, tea-lead rollers, solderers, and the like.