CHLORINE. 
§§ 51 . 52 -] 
opened. Two hours afterwards the men go in to pack the powder. 
The packers, in order to be able to work in the chambers, wear a 
respirator consisting of about thirty folds of damp flannel ; this is tightly 
bound round the mouth, with the nostrils free and resting upon it. The 
men are obliged to inhale the breath through the flannel and exhale 
through the nostril, otherwise they would, in technical jargon, be 
“ gassed.” Some also wear goggles to protect their eyes. Notwith¬ 
standing these precautions they suffer generally from chest complaints. 
§ 51. Effects. —Free chlorine, in the proportion of 004 to 0-06 per 
thousand, taken into the lungs is dangerous to life, since directly 
chlorine attacks a moist mucous membrane, hydrochloric acid is formed. 
The effects of chlorine can hardly be differentiated from those of hydro¬ 
chloric acid gas, and Lehmann found that 1-5 per thousand of this latter 
gas affected animals, causing at once uneasiness, evidence of pain with 
great dyspnoea, and, later, coma. The eyes and the mucous membrane 
of the nose were attacked. Anatomical changes took place in the 
cornea, as evidenced by a white opacity. 
In cases that recovered, a purulent discharge came from the nostrils, 
with occasional necrosis of the mucous membrane. The symptoms in 
man are similar ; there is great tightness of the breath, irritation of the 
nose and eyes, cough and, with small repeated doses, bronchitis with all 
its attendant evils. Bleaching powder taken by the mouth is not so 
deadly. Hertwig has given 1000 grms. to horses, 30 grms. to sheep and 
goats, and 15 grms. to dogs without producing death. The symptoms 
in these cases were quickening of the pulse and respiration, increased 
peristaltic action of the bowels, and a stimulation of the kidney secretion. 
The urine smelt of chlorine. 
Post-mortem Appearances. —Hypersemia of the lungs, with eccliy- 
moses and pneumonic patches, with increased secretion of the bronchial 
tubes. In the mucous membrane of the stomach, ecchymoses. The 
alkalescence of the blood is diminished and there may be external signs 
of bleaching. Only exceptionally has any chlorine smell been perceived 
in the internal organs. 
§ 52. Detection of Free Chlorine. —The usual method of detection is 
to prepare a solution of iodide of potassium and starch and to soak strips 
of filter-paper in this solution. Such a strip, when moistened and 
submitted to a chlorine atmosphere, is at once turned blue, because 
chlorine displaces iodine from its combination with potassium. 
Litmus paper, indigo blue or other vegetable colours are at once 
bleached. 
To estimate the amount of chlorine, a known volume of the air is 
drawn through a solution of potassium iodide, and the amount of iodine 
set free determined by titration with sodic hyposulphite, as detailed 
at p. 82. 
