METALLIC SALTS 587 



very peculiar cutaneous melanoses to which these conditions lead and which 

 have lately been much studied. The therapy must be strictly adapted to each 

 individual case. It is impossible to enter into its details. 



Poisoning by arseniureted hydrogen must be briefly referred to. This 

 is, of late, not rare in chemical laboratories and in chemical factories. The 

 cases run a severe course, but frequently terminate favorably. Jaundice, 

 hematuria, various spasms form the most important symptoms, i. e., the course 

 is entirely different from that of poisoning with the salts of arsenic! The 

 therapy consists only in strict prophylaxis: Avoidance of all chemical proc- 

 esses in open spaces in which arseniureted hydrogen can possibly develop. 



We now turn to another form of toxicoses : Poisoning with metallic salts, 

 metallism. From the enormous number of metallic salts which could be men- 

 tioned here, I shall only emphasize poisoning with lead and mercury as of 

 practical importance. 



Acute poisoning with salts of lead is, upon the whole, of comparatively 

 slight interest, but much more important are the chronic lbad toxicoses. 



Eegarding the former, a metallic taste, a sensation of dryness and burning 

 in the mouth and throat, and severe colic-like pains are the most important 

 symptoms; later obstinate vomiting occurs, and the vomited material often 

 shows a hemorrhagic discoloration. A diagnosis of acute poisoning with the 

 salt of lead cannot be certainly made from these symptoms, but the presence 

 of lead salts in the vomited material, the history, the corpus delicti, i. e., the 

 investigation of the salt which may be at hand, the fluid, etc., render the 

 diagnosis of acute lead poisoning possible. The immediate administration of 

 milk, of solutions of albumin, of sodium sulphate and magnesium sulphate 

 which reduce lead combinations to an insoluble lead sulphate, is recommended. 



It is most important for the physician to recognize chronic lead poisoning, 

 partly because of the frequency of its occurrence, and partly because it mani- 

 fests itself in such various ways. 



Lead poisoning from occupation, as in type-setters, painters, gas-fitters, 

 etc., is usually preceded by symptoms of lead colic: The patients are seized 

 with paroxysms of severe cutting pains in the abdomen, an attack in its great- 

 est intensity rarely lasting longer than a quarter of an hour, and after a 

 shorter or longer interval the severe paroxysms of pain set in anew. The 

 abdomen is retracted, there is constipation, the pulse is slow. The physician 

 must act at once. A lukewarm bath will often relieve the paroxysms of pain 

 in the briefest time; but the patient should not be allowed to suffer, and if 

 this is not effective, morphin subcutaneously should be employed ; 0.005 gram, 

 certainly 0.01 gram, hypodermically employed, will in a short time relieve 

 the attack. But the serious symptoms of chronic lead toxicosis can only be 

 averted if the patient, in the future, carefully avoids contact with combina- 

 tions of lead or working with salts of lead. If he fail to do this, the first 

 attack is succeeded by a second, a third, etc., and the serious tragedy of chronic 

 lead poisoning begins. 



Sometimes, besides the pale appearance, the excruciating pains m the 

 joints (arthralgia), paresthesia, various disturbances of sensation torment the 

 patient; in many cases he is spared these symptoms, but weakness m the 



