Make the test fluid fresh, as follows: Sulphate of copper, five grains; neutral tartrate of potash, ten grains; liquor potassa, two drachms. Mix these ingredients, and an intensely blue, clear fluid will be formed. Put a small quantity of this in the test tube and boil; while at the boiling point add the suspected urine, drop by drop, until equal in quantity to the test fluid; if sugar be present in quantity, it will form a precipitate of a red or orange color. The copper and alkaline fluids should be kept in separate bottles until about to be used, so as to have the test fluid fresh

Small quantities of sugar, such as less than 3 parts in 1000, present various anomalies. In such cases the uric acid and coloring matters of the urine have a reducing power, and therefore the copper precipitate is never red, but yellow, or, in fact, any intermediate shade, from the deep blue of the test fluid, through green to yellow. Again, if the urine is highly phosphatic, boiling with the alkaline solution may throw the phosphates, forming with the copper deposit, reduced by the normal urinary ingredients at the same time, a precipitate resembling the deposit of copper produced by sugar. In that case, we must. decolorize the urine by passing it repeatedly through a filter of animal charcoal: Also we must in all cases remove the albumen by boiling and filtration.

The Bismuth, Or Boettger's Test, may be used to confirm either of the foregoing tests, as follows: Take about a drachm of urine, freed from albumen, in a test tube, and add an equal amount of liquor potassa, and then about two grains of the subnitrate of bismuth. Boil for a minute or two, and if sugar is present, the bismuth will be changed to some color between black and gray, according to the large or small amount respectively of sugar in the urine.

Hylander's Test.*

℞ Bismuthi subnitratis.......3 ss

Sodii tartratis..........3 j

Solutionis potassae causticae (8%) iijss

M. Let stand twenty-four hours, and then filter through glass wool.

Put into a test tube 160 minims of urine and sixteen minims of the solution, and heat. If sugar be present, there will be a black precipi tate.

This solution will keep more than a year, and will, says Notel, "detect sugar in the proportion of 1 to 400."

Dr. William Roberts' Fermentative Test is used to determine the number of grains of sugar present in an ounce of diabetic urine, as follows. "(1.) Four ounces of urine are placed in a twelve-ounce vial, or special tube manufactured for the purpose, with a lump of German yeast of the size of a walnut. (2.) The vial is then loosely corked or covered with a glass slide, and placed in a warm place to ferment. (3.) A companion vial filled with the same urine, say a three-ounce vial, is tightly corked and placed beside the fermenting vial. (4.) In about twenty-two hours, when fermentation has ceased, the two vials are removed to a cooler place. (5.) Two hours after - or twenty-four hours from the beginning of the experiment - the contents of the vials are separately poured into two cylindrical glasses, and the density of each is estimated. (6.) The difference in specific gravity of the two is thus ascertained, and every degree of density lost indicates one grain of sugar, per fluid ounce, of the urine examined, "f