The halogens may be estimated by ignition with quicklime, or by heating with nitric acid and silver nitrate in a sealed tube.
Quicklime should not be used, as it dispels the greater part of the ammonia.
In the first method the substance, mixed with quicklime free from chlorine, is heated in a tube closed at one end in a combustion furnace.
In the case of poorer interments the destruction of the body was, on the contrary, often accelerated by the use of quicklime.
At this stage as a rule some rich slags of a former operation are added and a quantity of quicklime is incorporated, the chief object of which is to diminish the fluidity of the mass in the next stage, which consists in this, that, with closed air-holes, the heat is raised so as to cause the oxide and sulphate on the one hand and the sulphide on the other to reduce each other to metal.