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Scientific Proceedings (ioo). 



in cases not properly treated. Milder lesions may show only 

 the earlier stages of hyperemia, vesication or pigmentation. In 

 general the injuries may be classed as burns of first, second or 

 third degree. Following extensive hyperemias in human skin a 

 most marked pigmentation, exceeding in degree the most marked 

 forms of solar tan may be quickly developed and fade slowly. 

 This pigmentation may be diffuse or spotted. In human skin 

 vesication is pronounced; in animals the cutaneous lesions are 

 characterized by the development of marked subcutaneous edema 

 in the injured area. The fluid of the vesicle or of the edema is 

 nonirritating when applied to uninjured areas. In the case of 

 human skin frequently exposed to very dilute concentrations 

 (only perceptible by odor), an eczematous itching condition 

 between the fingers, on the genitals, etc., may develop; rubbing 

 or scratching of the itching part may lead to the quick develop- 

 ment of a blister or superficial eschar (Nikolsky's sign). Such 

 interdigital lesions in laboratory workers may resemble clinically 

 those produced by the itch mite. Cutaneous areas injured by 

 mustard gas are rendered more susceptible to trauma or other 

 forms of injury, including new exposures to mustard gas. This 

 local susceptibility is, however, a general one, and not a specific 

 lowered resistance to the action of dichlorethylsulphide. Sub- 

 cutaneous injections of pure dichlorethylsulphide produce painless 

 eschars, followed by dry sloughing, with edema less marked than 

 in the case of external cutaneous application ; a hypostatic edema 

 may develop on the animal's belly when injected in the back. 

 In the tissues at the site of the injection and in the hypostatic 

 edema mustard gas may be present for some days after the injec- 

 tion, as shown by odor and physiological reaction. The resolution 

 of mild skin injuries is often attended by troublesome itching. 

 Healing of the deep cutaneous eschars is very slow; during the 

 healing of extensive deep lesions the patients complain of a sensa- 

 tion of tightness or contraction of the skin; large scars may be 

 produced resembling those resulting from deep thermal burns. 

 The hair may be lost; but when regenerated they may be white 

 in color. 



Eye. — Upon the cornea mustard gas exerts an especially 

 injurious action, particularly at the vertex. Within ten to fifteen 



