On. Nitrat of Silver, as a Test of Arsenic. 121 



quite as exhilarating when cold as when it is taken hot, 

 whv should it not be made to supply the place ot those 

 pernicious drams of spirituous liquors, which do so 

 much harm ? 



" Halt' a pint of good cold cofFue, properly sweetened, 

 which would not cost more than halt a pint of porter, 

 would be a much more refreshuigand exhilarating draught ; 

 and would no doubt be incomparably more nourishing. 



'* How much then must it be preferable to a dram of 

 gin! 



" The advantages and disad^^antages to agriculture and 

 commerce, which would arise from the inlioduction of a 

 new beveraiie for supplying the place of malt liquors and 

 ardent spirits distilled from grain, must be estimated and 

 balanced by tho^e v\h()se knowledge of political CEcononiy 

 fits them for detei mining these most intricate and impor- 

 tant quebtions." 



This incenious Essav also presents descriptions (with 

 engravin<is) of elegant cofiee urns ; but as these are desiined 

 for" the opulent, we beg to refer for further particulars to 

 the Count's Eighteenth Essav. 



XVIII. Some 'Remarks on the Use of Nitrat of Silver^ for 

 the Detection of mimite Portions of Arsenic. By Alex. 

 Marcet, M.D. F.R.S. one of the Pkysicians to Guy's 

 Hospital *. 



Xn the interesting account of the poisonous effects of arse- 

 nic, presented to the Society bv Dr. Roget, and published 

 in the second volume of the Medico- Chirurgical Transac- 

 tions t> the author has recommended, for the detection of 

 this poison, a test which I pointed out to him, and which, 

 from a variety of experiments which we tried together, 

 with a view to ascertain its comparative merits, we were 

 induced to consider as the most effectual of all the tests 

 hitherto used for that purpcjse, I he method consists sim- 

 ply in adding in succession, to the fluid suspected to con- 

 tain arsenic, minute quantities of solutiwus of ammonia and 

 of, nitrat of silver; by which means, if the sinallest quan- 

 tity of arsenic be present, a dense yellow precipitate will be 

 produced. 



• From thf third volume (if the Medico-Cliirurgical 1 ransactions, pub- 

 liblicd by die MLdica! and CIiirur;^ical Society of London. 



t I lalce this iipporlunity of slating, at Ur. Rogtt's request, that the pa- 

 tient, whose case he there rclaltd, coDiptclely recovered her health, ;:iul has 

 rcuiuiiicd well crer siacc. 



All 



