84 POISONS : THEIR EFFECTS AND DETECTION. [§§ 53, 54. 
III.—Hydric Sulphide (Sulphuretted Hydrogen). 
§ 53. Hydric sulphide, SH 2 , is a colourless, transparent gas of specific 
gravity 1-178. It burns with a blue flame, forming water and sulphur 
dioxide, and is soluble in water ; water absorbing about three volumes 
at ordinary temperatures. It is decomposed by either chlorine gas or 
sulphur dioxide. 
It is a common gas as a constituent of the air of sewers or cesspools, 
and emanates from moist slag or moist earth containing pyrites or 
metallic sulphides ; it also occurs whenever albuminous matter putre¬ 
fies ; hence it is a common constituent of the emanations from corpses of 
either man or animals. It has a peculiar and intense'odour, generally 
compared to that of rotten eggs ; this is really not a good comparison, 
for it is comparing the gas with itself, rotten eggs always producing 
SH 2 ; it is often associated with ammonium sulphide. 
§ 54. Effects. —Pure hydric sulphide is never met with out of the 
chemist’s laboratory, in which it is a common reagent either as a gas 
or in solution ; so that the few cases of poisoning by the pure gas, or 
rather the pure gas mixed with ordinary air, have been confined to 
laboratories. 
The greater number of cases have occurred accidentally to men 
working in sewers, or cleaning out cesspools and the like. In small 
quantities it is always present in the air of towns, as shown by the 
blackening of any silver ornament not kept bright by frequent use. 
In the construction of a graving dock at Hebburn-on-Tyne, July 1902, 
three workmen lost their lives through breathing SH 2 . They had to 
enter a large iron caisson, the excavation at the bottom of which had 
reached some old alkali waste, and the water, as subsequent analysis 
showed, contained 12-2 volumes per cent, of SH 2 . The first workman 
had been in twenty minutes when screams were heard ; a second man 
went to his assistance, shouted and fell to the bottom ; the same fate 
befell a third. The post-mortem examination showed the heart normal, 
right side flaccid and empty, left hard and firmly contracted. No 
odour of hydric sulphide in the body. Lungs pale and oedematous. 
Liver dark. Blood dark and liquid. The spectroscope showed no 
carbon monoxide bands. 1 
It is distinctly a blood poison, the gas uniting with the alkali of the 
blood, and the sulphide thus produced partly decomposing again in the 
lung and breathed out as SH 2 . In some sense it acts as a reducing 
agent, for it robs cells of loosely bound 0, and therefore kills them by 
deprivation of oxygen ; it also attacks labile groups, as it substitutes in 
the aldehyde group sulphur. 
1 “ Fatalities to Workmen breathing Sulphuretted Hydrogen,” by Thos. Oliver, 
M.D., Lancet, Jan. 20, 1903. 
