The best and most modern methods of the examination of urine as required in medical practice / by W. Henry Kesteven.

  • Kesteven, W. Henry (William Henry)
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: The best and most modern methods of the examination of urine as required in medical practice / by W. Henry Kesteven. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    divisions, while the stoppered tube contains the ferric acetate standard solution. Now dilute the dark red liquid in the graduated tube with water till the colour is nearly equal in tint to that of the standard in the adjacent tube. Confirm the identity of the tints by transferring some of the diluted liquid to one of the flat-bottomed tubes, of which it should be made to fill about one inch in height, and comparing with an equal depth in the standard solution by looking through the two liquids upon a piece of white paper in a good light. The tints being identical transfer again to the saccharimeter and read off the level of the liquid. Each division above io = o.i grains per fluid ounce : thus 13 divisions = 1.3 grains per fluid ounce, 30 divisions = 3 grains per fluid ounce, etc., etc. If more than eight grains per fluid ounce is indicated dilute another portion of the urine ten times by delivering 5cc. from the measure into the 50CC. diluting flask and filling up to the graduation mark with water and repeat the analysis as before, employing sixty minims of the picric acid solution. In this case each division on the saccharimeter above 10 divisions indicates one grain of sugar per fluid ounce : thus, dilution from 10 up to 58 divisions indicates that the urine contained fifty-eight grains to the fluid ounce. There is a slight drawback to this test in that the colour produced by an undiluted specimen of urine which contains anything over five or six grains of sugar to the ounce and that produced by a diluted specimen containing about ten grains to the ounce are very similar, so that if in examining an undiluted specimen we find it necessary to dilute it over the division marked 60 we cannot be sure of our result. Dr. Johnson recognizes this in advising that if the urine contains over eight grains to the ounce, that it requires dilution above the 80th division, it should be diluted and tested again, but he fixed the limit for this necessity too high : experience shows that he should have put it at the figure 60. (4) OXALIC ACID. This substance is found in urine in the form of calcium oxalate. Although this salt is present in a greater or less degree in the vast majority of urines it cannot be regarded as a normal constituent. Its presence is said to be due to a deficient oxidation of organic material. It may be detected and the amount estimated by the use of phenol-phthalein and caustic soda. On the addition of caustic soda to a solution of phenol- phthalein a red colour is developed, but if oxalic acid is
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