Lead-poison sometimes enters the system continuously, for a long period, but in proportions too minute to produce the effects which we identify as an attack of lead-colic. I believe that for the production of the latter complaint it is necessary that the poisoning shall be sufficiently intense completely to paralyze a considerable piece of bowel, thus altogether hindering peristalsis, or, rather, making the peristaltic acts of the non-paralyzed portions above worse than fruitless. But there is a minor degree in which it may happen that the local affection (owing, I believe, to a less extensive deposit of lead in the bowel) does not reach the decidedly paralytic stage; the state then is one of irregular and painful spasm of individual fibres (quite possibly intermingled with paralysis of a few others), and the practical result is irregularity of evacuation--now diarrhoea, and again constipation--and the frequent recurrence of twinges of pain that are easily mistaken for abdominal neuralgia. Such symptoms as these are nearly always found to have occurred, if proper inquiry be made, in those examples of chronic lead-poisoning in which the toxic process goes on to the development of epilepsy, or marked symmetrical paralysis of the wrist-extensors, without the patient having ever suffered an attack of ordinary colic. In these slow and insidious cases the constitutional affection may not have reached the height at which the complexion and general aspect of the patient suggests metallic poisoning: and the case may present very neuralgia-like features. The absence of the _points douloureux_ is not, as we have seen, conclusive against neuralgia in its early stages. It is therefore an excellent rule, in all cases of chronic recurrent spasmodic pain in the abdomen, especially in men, to investigate the possibilities of lead-poisoning; and, if the slightest suspicious appearance of the gums be found, this track of inquiry must be followed up exhaustively before we abandon the idea. The absence of all special neurotic history in a patient's family should increase our suspicions respecting pains of this character that continue with an obstinacy which makes it unlikely they are due to improper food.