gQ MEDICAL JURISPRUDENCE Fig. 22.—Reconstructed Pelvic Girdle, (From a photograph lent kindly by Dr. M. A. Khan.) In cases of suspected poisoning "by some mineral, e.g. arsenic, all the available ashes and burnt bones should be preserved for chemical analysis, as it is possible to detect arsenic in large pieces of burnt bones mixed with ashes in cases of poisoning by arsenic despite its volatility for the following reasons 22: — (a) Much of the arsenic in bones is converted into arsenates, partially replacing the phosphates of the bones. Arsenates are non-volatile; hence arsenic can be detected in the bones even after strong heating for a long time. (b) Even if all the arsenic were present in the bones in the form of arsenic trioxide or some other volatile form, all the arsenic is not likely to be lost during the process of cremation, as complete combustion of a body does not, as a rule, occur in India ; hence some of the volatilized arsenic is liable to be condensed on the cooler parts of the unburnt funeral pyre, where its presence may be detected. (c) When arsenic trioxide is heated with salts of sodium or earth group, part of the arsenic is converted into arsenate and becomes non-volatile. It is reported that the Chemical Examiner of the United and the Central Provinces was able to detect arsenic in 19 out of 97 samples of ashes and burnt bones received for chemical analysis in his laboratory at Agra between the years 1921 and 1940, while the Chemical Examiner of the Punjab detected arsenic in 10 out of 92 samples of ashes and burnt bones examined between the years 1924 and 1931. I quote the following from my case-book: — 1. In August 1918, a sealed box from Police Station Itaunja, District Lucknow, was brought for examination. The box contained a skull, a pelvis with two femurs attached, two tibiae (the extremities of which had been gnawed through by animals), three right and three left ribs and a piece of a rib (the ends of which had been torn away by animals) and ten dark hairs, each about ten to eleven inches long. From the exami- nation of these bones, especially of the pelvis and the hairs it was ascertained that the 22. Chakravarti, S. K, Faruqi, M. Z., and Ganguli, K. R., Ind. Med. Gaz., Dec. 1941, pp. 722-724.