394 LEAD POISOXIXG. 



of the offending material, only leaving tlie body during tlie 

 natural changes which regularly occur in every tissue. 



Causation and Modes of Induction. — The causes of plumbism 

 in any form are of necessity the entrance into the system of 

 lead in its metallic form or in some of its various compounds, 

 either alone or in association with other materials. That 

 metallic lead may be conveyed into the digestive organs with- 

 out any hurtful results following may be allowed ; that it may, 

 and often does, by the combinations and forms which it then 

 assumes, prove the original factor from which serious derange- 

 ment and textural change may proceed ' is equally certain. 

 Before these undesirable results can follow from the ingestion 

 of the metal, some changes must occur by which the com- 

 pounds, formed through the action on the metal of the natural 

 and other fluids in the stomach, are rendered capable of trans- 

 mission into the blood and lymph-stream, and thus carried to 

 the various organs and tissues of the body. What the exact 

 compounds of the metal are is somewhat doubtful. It is thus 

 far certain, however, that by the action of the different fluids 

 on the innocuous and insoluble metal there is produced a 

 hurtful and necessarily soluble compound of lead, which may 

 only be developed in this form prior to a further and more 

 perfect transformation. 



Probably the steps in the chemical change are not more 

 uniform than are the ultimate products themselves. The 

 modes by which lead and compounds of lead enter the system 

 vary somewhat. With cattle they are often directly conveyed 

 into the stomach in the form of refuse fabrics containing lead 

 compounds, or as the unmixed compounds themselves. With 

 horses this is less likely, as they are decidedly averse to par- 

 take of unnatural and extraneous matters, alone, or when 

 mingled with their food. 



I have, however, met with several serious cases of lead- 

 poisoning in horses, some of which terminated fatally, from 

 the animals, in mischief or in play, picking off" and swallowing 

 putty containing a considerable amount of red lead, which had 

 been used in executing certain repairs connected with the 

 water-supply of the yard where they were located. In another 

 instance the offending agent Avas newly painted wood-work, 

 which, by assiduous licking and gnawing over a period of two 



