THE FATE OF ARSENIC IN THE BODY. 645 



(.16 per cent. AS2O3), whereas in Pitchford's dip soft soap 

 and paraffin were also present. 



Further consideration of the significance of these data, in 

 regard to the theory of tick destruction by arsenical dips, is post- 

 poned until further data are obtained. Meanwhile we are satis- 

 fied that the earlier figures for the amount of arsenic fixed in 

 the skin of dipped animals are vastly too high. Worked out for 

 the total superficies of the beast, the amount of arsenic fixed 

 in the shaved hide, or skin proper, would be about 7 to 12 grams 

 from Pitchford's data, but only o. 16 to 0.2 grams from our own 

 data. It is noteworthy that the small amount of fixed arsenic 

 recorded by us is much the same ten days after dipping as it is 

 one day after. 



The differences recorded for the hair and scurf are less 

 worthy of comment since the arsenic concerned is mainly arsenite, 

 which has dried on, and the presence of soap in Pitchford's dip 

 might account for the higher figures for merely adherent arsenic. 



For the sake of getting an approximate idea of the amount 

 of arsenic adhering to the hair and scurf, the carcase of another 

 regularly dipped ox was examined. One square foot was marked 

 ofl (Ihind quarter), clipped, then shaved, and then cut out. 



The clipped hair was soaked in water ifor half an hour, 

 filtered, and washed. The filtrate showed .052 gm. AsgOg, and 

 the rinsed hair showed .028 gm — per square foot. The residue 

 of short hair and scurf removed by shaving (with soap) showed 

 .011 gm. AsgO, per square foot more or less "fixed," and .035 

 gm. readily removed by washing with water. 



The greater proportion of the arsenic in the hair and scurf 

 (total .126 gm. per square foot) is therefore not fixed," but 

 merely adherent. The shaved hide, or skin proper, showed only 

 .006 gm. AS2O3 per square foot, of which .0033 was present in 

 the epidermis, and .0027 gm. in the underlying connective tissue. 



Elimination of Arsenic after Oral Dosing and after 

 Intravenous Injection. 



Oral Dosing : Two experiments were carried out — one on 

 a sheep* and one on a horse — in which known doses of sodium 

 arsenite were administered, and the daily elimination in faeces 

 and urine then followed for eight days. Table 5 shows the 

 results : 



*For extensive data on the sheep, loc. cit. i. 



