296 On Cutaneous Absorption. 



EXPERIMENT X. 



To throw additional light on the query, did the co- 

 louring matter of the blood enter the urine, and produce 

 the red appearance exhibited in the 1st, 2nd, and 4th 

 experiments ?, I agitated a small bit of crassamentum, 

 with a quantity of pale, recent urine, until it acquired 

 nearly the colour of the urine of the fourth experiment. 

 The urine thus coloured was tested with the solution of 

 potash, but no change followed, except a diminution of 

 colour, in proportion to the quantity of the solution add- 

 ed. The sulphat of iron did not change its appearance. 



EXPERIMENT XI. 



With a view to compare the appearances of the urine 

 after taking madder internally, with those which 

 followed its external application, I took, March 31, 

 two ounces of a strong infusion of madder. At this 

 time the urine was discharged : it was pale, and was 

 not altered by the addition of the potash. At the end 

 of two hours, the urine was again discharged : it was 

 pale, as before, and was not affected by the potash. At 

 the end of five hours, the urine drawn was faintly ting- 

 ed with a reddish hue. The solution of the potash 

 sensibly reddened it. Succeeding portions were pale. 



EXPERIMENT XII. 



April 1, half past 3, P. M., I took six ounces of a 

 strong infusion of madder. The urine discharged at 



