Lead is peculiarly a cumulative poison, and post-mortem analyses of viscera show that it may be stored up in certain parts of the body, more especially in the bone and red bone marrow and brain, and to some extent in the liver, spleen, and kidneys. Any circumstance, therefore, that temporarily interferes with the ordinary channels through which lead is excreted may determine the presence of a much larger quantity than usual of the metal in circulation in the body; and if in addition an increased quantity of the poison be inhaled, more or less acute symptoms follow. The localization of the deposit of lead is therefore of some importance. Meillère and Richer[4] give an analysis of various organs of the body, but their results are not in accord with the majority of other observers. They found that the hair particularly contains a large quantity of lead. They do not seem to have examined the bones. Next to the hair, the liver seems to have contained the largest amount. Wynter Blyth[5] found 117·1 milligrammes of lead in the brain of a person who died of encephalopathy. In another case he found 0·6 gramme in the liver, 0·003 in the kidney, and 0·072 in the brain. Hougounencq[6] examined the organs of a person who died from lead poisoning, and found the largest amount of lead in the large intestine. Large intestine 0·2150 gramme. Small intestine 0·0430 „ Liver 0·0050 „ Brain 0·0008 „ In the lung, stomach, kidney, and heart, only traces were found. Dixon Mann[7] describes some experiments in which potassium iodide was given in cases of chronic poisoning, and during the whole of the experiments the fæces and urine were analyzed three times a week. He found by this means that a considerable amount of lead was being eliminated by the intestine. He therefore administered 2 grammes of lead acetate three times a day for five days to a patient, and he found that the fæces contained 0·1762 gramme the first day, 0·17411 gramme the second day; the fourth day it had fallen to 0·0053 gramme, and on the sixth day to 0·0006 gramme. The largest amount at any one time in a day obtained from the urine was only just over 0·001 gramme; the average amount found in the case of chronic poisoning was about 3 milligrammes, whereas the greatest amount at any one time in the urine was only 0·9 milligramme. The quantity of lead present in the brain necessary to determine acute poisoning is not known, and it is probable that an extremely minute quantity will produce very serious effects; and in support of this may be quoted a number of observations in which search has been made for the metal in persons who have died of diseases affecting the brain associated with other symptoms of poisoning, and yet post-mortem examination of the brain by chemical methods has not revealed the presence of any lead whatever. In the case reported by Mott (see p. 71), no lead at all was recognized in the brain.