TEST 



536 



TEST 



I : 30,000 copper-saft solution added to I c.c. colorless 

 concentrated acid still affords the reaction. Reagent 

 may be replaced by a solution of KBr in orthophos- 

 phoric acid. Delicacy of reaction somewhat impaired 

 by presence of free bromin ; on driving off latter by 

 heat, however, the color is observed. (Merck. ) 

 Sabrazes-Deniges* Test-paper for Iodin. Boil 1 

 gm. starch with 40 c.c. water, cool, and add 0.5 gm. 

 sodium nitrite. Apply paste to both sides of heavy 

 unsized paper. The dry paper is moistened with 

 liquid to be tested, and moistened spot wetted with I 

 drop 10 f c H 2 S0 4 — if iodin (iodid) is present, a blue 

 color develops. (Merck.) T., Saccharimeter. A 

 solution of dextrose rotates the plane of polarized 

 light to the right. Saccharin. See Bornstein, 

 Schmitt. Salicylic Acid. See Hidenour, Robinet, 

 Spicca. T., Salkowski's, for Creatinin. See T. , 

 WeyVs (Illus. Diet). T., S.'s, for Indol. To the 

 indol solution add a few drops of nitric acid, and then, 

 drop by drop, a 2% solution of potassium nitrite. 

 The presence of indol is evinced by a red color, and 

 finally by a red precipitate of nitrosoindol nitrate. 

 T., S.'s Modification of Hoppe-Seyler's, for 

 CO in Blood. Add to the blood to be tested 20 

 volumes of water and an equal quantity of a sodium 

 hydrate solution of specific gravity 1. 34. In the pres- 

 ence of carbon monoxid the mixture will soon become 

 milky, changing to bright red. On standing, red 

 flakes collect on the surface. Normal blood treated 

 in this way gives a dirty brown coloration. T., S.'s, 

 for Peptone in Urine. Acidulate 50 c.c. urine with 

 HC1, and precipitate with phosphotungstic or phospho- 

 molybdic acid. Wash the precipitate, warm on water- 

 bath, dissolve with a little NaOH, and add a few 

 drops 1% to 2% CuS0 4 solution. In presence of pep- 

 tone, a red color appears. The author amends this test, 

 since he finds that the presence of urobilin may occasion 

 a precipitate and give the biuret reaction like album- 

 ose; if, therefore, urobilin is present, it may first be re- 

 moved from the phosphomolybdic precipitate before 

 the biuret reaction is applied. (Merck.) T., Sal- 

 kowski-Leubes', for Mucin in Urine. Treat urine 

 with 2 volumes absolute alcohol, collect precipitate 

 and re-dissolve in water. The solution gives a cloud 

 with acetic acid insoluble in excess, but soluble in 

 HC1 or HNOj. (Merck.) T., Sandlund's, for 

 Iodin in the Urine. Treat 5 c.c. of urine with 

 I c.c. of sulfuric acid (1:5) and 2 or 3 drops of sodium 

 nitrate solution (r.o gm. in 500 c.c), and shake with 

 carbon bisulfid. In the presence of iodin (up to 

 0.001%) the carbon bisulfid becomes colored. San- 

 tonin. See Pain. T., Saul's, for Eserin. If a 

 solution of eserin, or one of its salts, be heated to 

 boiling, and a few drops of strong HN0 3> added, an 

 orange-colored liquid is obtained, which, on adding 

 NaOH in excess, yields an intensely violet solution. 

 The violet color is changed to pale-orange by acids, 

 and restored by alkalis. (Merck.) T., Saul's, for 

 Tannin. To about 0.015 g m - tannin in 3 c.c. water 

 add 3 drops of 20'r alcoholic solution thymol, and 

 then 3 c.c. strong H a S0 4 — gallotannic acid yields a 

 turbid rose-colored solution ; gallic acid remains prac- 

 tically uncolored. (Merck.) T., Savalle's, for 

 Fusel Oil in Alcohol. Heat alcohol with an equal 

 volume of concentrated H 2 S0 4 until boiling commences 

 — fusel oil is indicated by the formation of a brown 

 color; all aldehyds and even higher alcohols give this 

 reaction. If the latter are to be tested for, the alde- 

 hyds may be removed by heating for half an hour with 

 a little metaphenylenediamin hydrochlorate and subse- 

 quent distillation ; the distillate thus freed from alde- 

 hyds is tested with H 2 S0 4 . If the quantity of fusel 



oil is slight, IO to 20 drops of a I : 1000 solution fur- 

 furol may be added, and then a pink color is developed, 

 if higher alcohols be present, on heating with H 3 S0 4 . 

 Test may be employed quantitatively for the colorimet- 

 ric determination of fusel oil. (Merck.) T., Scent, 

 for plumbing. It is made by putting into the pipes a 

 quantity of some pungent chemical, such as pepper- 

 mint oil, the odor of which will escape from the de- 

 fects in the pipes if there are any [Price]. Cf. 

 Drai7i-tester, Hudson? s. T., Schacht's, for Benzoic 

 Acid. The acid from Siam benzoin decolorizes an al- 

 kaline solution KMn0 4 , but that from other sources 

 merely alters the color to green. (Merck.) T., 

 Schaer's, for Blood. See T., HiihiiefehV s (Illus. 

 Diet.). T., Schafer's, for Cinchonidin in Quinin 

 Sulfate. The tetrasul fate test : it is dependent upon 

 the slight solubility of cinchonidin tetrasulfate in alco- 

 hol. Dissolve I gm. of quinin sulfate in 9 gm. of 

 absolute alcohol and 3 gm. of 5% sulfuric acid. 

 Allow this to stand for a day with occasional shaking, 

 when any cinchonidin present will have separated out 

 as tetrasulfate. If this precipitate is dissolved in 

 water and precipitated with a caustic soda solution, 

 pure cinchonidin of melting-point 199 C. may be ob- 

 tained. T., S.'s, for Naphthol-yellow in Cakes, 

 Pastry, etc. Break up into crumbs 10 to 20 gm. of 

 the material to be tested and warm with 40 c.c. of al- 

 cohol (50 to 60% by vol.). Naphthol-yellow colors 

 the alcohol yellow ; upon the addition of hydrochloric 

 acid this color disappears ; but if the color were pro- 

 duced by saffron, it would remain. T., S.'s Quinin. 

 Dissolve in 35 c.c. of boiling water, I.O gm. crystal- 

 lized or 0.85 gm. anhydrous quinin sulfate and add a 

 solution of 0.3 gm. of crystallized neutral potassium 

 oxalate in 5 c - c - of water; then make up the whole 

 with distilled water to 41. 3 gm. Now place the ves- 

 sel for half an hour in a water-bath of 20 C, shaking 

 occasionally, and lastly filter through glass-wool. The 

 freedom of the quinin from an allied alcohol is evinced 

 by the absence of any turbidity on the addition of a 

 drop of a caustic soda solution to 10 c.c. of the filtrate. 

 S.'s Reaction for Identifying Nitrites in the 

 Urine. Decolorize 3 or 4 c.c. of urine with animal 

 charcoal and then treat with an equal volume of dilute 

 acetic acid (1 : 10) and 2 drops of 5% potassium fer- 

 rocyanid solution. In the presence of nitrites the 

 solution is colored yellow. Scheele's Reagent for 

 arsenous acid. A solution of copper sulfate in an ex- 

 cess of ammonia water; this yields a light green pie 

 cipitate with arsenites. Scheibler's Reagent for 

 Alkaloids in Phosphotungstic Acid. Prepare the 

 solution by dissolving 100 gm. of sodium tungstate 

 and 60 to 86 gm. sodium phosphate in 500 c.c. of 

 water acidulated with nitric acid ; or, according to 

 Otto, by simplv adding phosphoric acid to a solution 

 of sodium tungstate. It produces precipitates similar 

 to those caused by phosphomolybdic acid. Schell's 

 Reagent for Cocain. Upon mixing cocain hydro- 

 chlorate with calomel and moistening with a little 

 water (even breathing upon the powder is sufficient), 

 the mixture will be blackened by partial reduction of 

 the mercury salt. Schlagdenhauffen's Reagent 

 for Distinguishing Alkaloids from Glucosids. A 

 mixture of equal parts of a3 f r solution of guaiac resin 

 and a saturated mercuric chlorid solution. Only alka- 

 loids give a precipitate with this reagent in the cold or 

 at 6o° to 79 C. T., Schlesinger's, for Urobilin. 

 Equal parts of the urine and a 10 r ' r solution of zinc 

 acetate in absolute alcohol are mixed and then filtered ; 

 if urobilin is present, the filtrate shows a beautiful flu- 

 orescence with distinct absorption bands. Other pig- 

 ments in the urine do not disturb the reaction, except 



