. The examination of the urine of the horse and man . changes the color of the copper solution, but thisdoes not indicate sugar. Benedicts Modification of Fehlings Test. Greaterdelicacy and accuracy are claimed for this test. • There aretwo solutions as in Fehlings. The first is prepared bydissolving grams of cupric sulphate in a smallamount of water and made up to 500 cc. The second bydissolving 100 grams of anhydrous sodium carbonate and173 grams of Rochelle salt dissolved in water and made upto 500 cc. These solutions should be preserved separatelyin rubber-stoppered bottles and mixed
. The examination of the urine of the horse and man . changes the color of the copper solution, but thisdoes not indicate sugar. Benedicts Modification of Fehlings Test. Greaterdelicacy and accuracy are claimed for this test. • There aretwo solutions as in Fehlings. The first is prepared bydissolving grams of cupric sulphate in a smallamount of water and made up to 500 cc. The second bydissolving 100 grams of anhydrous sodium carbonate and173 grams of Rochelle salt dissolved in water and made upto 500 cc. These solutions should be preserved separatelyin rubber-stoppered bottles and mixed in equal volumeswhen needed for use. This is done to prevent deteriora-tion. To 2 cc. of Benedicts solution in a test tube add 6 distilled water and not more than 7 to 9 drops of theurine under examination. Boil the mixture vigorously for15 or 30 seconds and allow it to cool to the room tempera-ture. If sugar is present in the solution a precipitate willform which is often hluish-green or green at first, especially vN\ ^Jv/V\*JI: ^. 39 if the percentage of sugar is low, and which usually be-comes yellowish on standing. If the sugar present this precipitate generally forms at or below theboiling point, whereas, if less than of sugar is pres-ent the precipitate forms more slowly and generally onlyafter the solution has cooled. Benedict has further modified the test by making asingle solution which does not deteriorate upon longstanding. The formula is as follows: Cupric Sulphate grams Sodium Citrate Sodium Carbonate (anhydrous) Distilled Water to cc. ^ With the aid of heat the sodium citrate and carbonateare dissolved in about 600 cc. of water. Pour (through afolded filter if necessary) into a glass graduate and makeup to 850 cc. The cupric sulphate is dissolved in about100 cc. of water and made up to 150 cc. The carbonate-citrate solution is poured into a large beaker and the cupricsulphate solution is added slowly, with consta
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