$6 SORBENTIA. Ar*. IV. t. 6. 9. 



crous fyflem. 1 was led to this conclufion from the following 

 confiderations. 



Firft. The efFedts of arfenic given a long time internally in 

 fmall dofes, or when ufed in larger quantities externally feem 

 to be fimilar to thole of other great ftimuli, as of wine or alco- 

 hol. Thefe are a bloated countenance, f welled legs, hepatic tu- 

 mours, and dropfy, and fometimes eruptions on the fkin. The 

 former of thefe I have feen, where arfenic has been ufed external- 

 ly for curing the itch •, and the latter appears on evidence in the 

 famous trial of Mils Blandy at Chelmsford, about forty years ago. 



Secondly. I faw an ague cured by arfenic in a child, who 

 had in vain previoufly taken a very large quantity of bark with 

 great regularity. And another cafe of a young officer, who had 

 lived in temperately, and laboured under an intermittent fever, 

 and had taken the bark repeatedly in confiderable quantities, 

 with a grain of opium at night, and though the paroxyfms had 

 been thrice thus for a time prevented, they recurred in about a 

 week. On taking five drops of a faturated folution of arfenic 

 thrice a day the paroxyfms ceafed, and returned no more, and 

 at the fame time his appetite became much improved. 



Thirdly. A gentleman about fixty-five years of age had for 

 about ten years been fubjedt to an intermittent pulfe, and to 

 frequent palpitations of his heart. Lately the palpitations 

 fe'emed to obferve irregular periods, but the intermiflion of eve- 

 ry third or fourth puliation was almoft perpetual. On giving 

 him four drops of a faturated folution of arfenic from a two- 

 ounce phial almoft every four hours for one day, not only the 

 palpitation did not return, but the intermiflion ceafed entirely, 

 and did not return fo long as he took the medicine, which was 

 three or four days. 



Now as when the ftomach has its action much weakened by 

 an over-dofe of digitalis, the pulfe is liable to intermit, this evin- 

 ces a direct fympathy between thefe parts of the fyflem ; and 

 as I have repeatedly obferved, that when the pulfe begins to in- 

 termit in elderly people, that an eruc~lation from the ftomach, 

 voluntarily produced, will prevent the threatened flop of the 

 heart ; I am induced to think, that the torpid ftate of the ftom- 

 ach, at the inftant of the production of air occafioned by its 

 weak action, caufed the intermiflion of the pulfe. And that 

 arfenic in this cafe, as well as in the cafes of agues above men- 

 tioned, produced its effects by Simulating the ftomach into more 

 powerful action ; and that the equality of the motions of the 

 heart was thus reftored by increafmg the excitement of the fen- 

 forial power of aflbciation. See Sect. XXV. 17. Clafs IV. 



iS. 



Arfenic* 



