MINEEAL OB INOEGANIC POISONS 



37 



one-tenth of the ingested dose proves fatal — i.e., about 

 60 grains. for the horse and ox, as against 600 to 700 grains 

 by the mouth. It will be observed that this dose is about 

 equal to that of dissolved arsenious acid by the mouth. 



The local effect of arsenic on mucous membranes is 

 caustic, with formation of sloughy gangrene. 



Absorption of dissolved arsenic from the mucous mem- 

 branes of the digestive tract is very rapid, and the irritant 

 effects are well marked with concentrated solutions. In 

 a recently investigated case of acute arsenical poisoning, 

 xir grain per ounce of unabsorbed arsenic was observed in 

 stomach contents, whereas the contents of the small in- 

 testines were almost free of arsenic. This illustrates the 

 rapidity of absorption and production of general toxic 

 effects. Similarly, in acute cases arsenic is speedily found 

 in the liver, although in less quantity than in subacute 

 or slow-poisoning cases. Interesting data bearing on this 

 point were obtained in investigating three cases of arsenical 

 poisoning by dip of Jersey cows. In Case I. death was very 

 rapid, within twenty-four hours of dosage ; in Case II., five 

 days ; and in Case III., seven days elapsed. The figures 

 tabulated show the proportions of arsenic in grains per 

 ounce found in the parts named : 



The noteworthy point is the evidence of the gradual 

 distribution of the poison over the alimentary system, and 

 its increasing accumulation in the liver. 



With the passage of time the quantity remaining in the 

 ingesta will dwindle. Thus, in a well-established case of 

 cattle poisoning by weed killer, investigated in 1906, the 

 arsenic was found to be very evenly distributed throughout 



