698 POISONS : THEIR EFFECTS AND DETECTION. [§§ 89 O, 891 . 
continued for twenty-four hours. In a case of mercury-poisoning Schumm 
found in the kidney 1-89 mgrm., liver 1 mgrm., pancreas -44 mgrm., 
and lung *4 mgrm.—dotal separated, 3-73 mgrms. 1 
§ 890. Separation of Mercury by Hydroxylamine.—Paul Jannasch 
( Ber ., 1898) has shown that mercury may be separated quantitatively 
from copper, bismuth, lead, nickel, cadmium, arsenic, antimony, and tin, 
by an ammoniacal solution of hydroxylamine. The mercury should 
be converted into chloride, and, to the hydrochloric acid solution, 
tartaric acid, ammonia, and hydroxylamine hydrochloride are added in 
excess, and the solution heated until the precipitation is complete ; the 
mercury is collected, redissolved in fuming nitric acid, the solution 
evaporated to dryness, the residue taken up with hydrochloric acid, and 
the mercury precipitated as sulphide. Mercury may be similarly 
separated from aluminium, chromium, or manganese in the presence of 
oxalic acid ; mercury and cobalt may also be separated by the addition 
of ammoniacal hydroxylamine to a slightly acid solution of their salts. 
§ 891. Detection of Mercury in the Urine.—One of the best 
methods is to acidify with concentrated hydrochloric acid, and add 
potassic chlorate in the proportion of about 1 grm. for every 100 c.c. ; 
the urine is heated until it no longer smells of chlorine, and then mixed 
with a dilute solution of stannous chloride ; in this mixture a piece of 
gilt platinum foil is placed for fifteen minutes, the foil heated with nitric 
acid, and the solution evaporated to a small bulk and then tested with 
hydrogen sulphide. This method will detect 0*07 mgrm. of mercury. 2 
Schumacher and W. Juny 3 use a similar process, but add sodium 
chloride, and after boiling with the hydrochloric acid and potassic 
chlorate, cool to 80° and add rasped zinc ; in about two hours the un¬ 
dissolved zinc is collected, washed, heated with dilute potassium hydrox¬ 
ide, and again washed. It is then dissolved in 50 c.c. of dilute hydro¬ 
chloric acid with the addition of potassic chlorate ; after boiling out 
most of the chlorine, the last traces are removed by the addition of 
alcohol. Hydrogen sulphide is added, the mixture made up to 100 
c.c., and the yellowish-brown colour compared colorometricaliy with 
standard solutions of mercuric chloride. 
Ernst Janecke (Zeit . /. anal. Chem., 1904) separates mercury from 
urine on the foregoing principles, obtaining the metal first on a spiral 
of copper wire. The wire is washed with hot water and air-dried. It 
is then put in a dry reagent tube, which is drawn out just beyond the 
wire to a capillary tube ; by means of strong heat the mercury is then 
1 Schumm also shows that a fluid capable of filtration can be obtained by digesting 
or incubating at 37° with an equal bulk of water to which, as an antiseptic, chloro¬ 
form is added. Under these circumstances in about a week auto-digestion, to a 
great extent, will have taken place. For the same purpose he also uses pepsin and 
hydrochloric acid ; but such time-consuming processes are hardly practical. 
2 Adolf Jolles, Zeit. anal. Chem., 1900. 3 Ibid., 1902. 
