A guide to the examination of the urine, intended chiefly for clinical clerks and students / by J. Wickham Legg.

  • John Wickham Legg
Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: A guide to the examination of the urine, intended chiefly for clinical clerks and students / by J. Wickham Legg. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    The heat is appUed until the upper portion of the ui'ine begins to boil, for although albumen, when in large quan- tity coagulates at a point far below boiling yet the pre- sence of a small quantity gives no precipitate below 212° F. The boiled stratum of fluid should now be carefully compared with the cool layer in the lower part, by hold- ing the test tube against the light: if any cloudiness or opacity be seen, it must not at once be concluded that albumen is present: but a drop or two of dilute nitric acid should be allowed to flow gently down the side into the tirine: the cloud, if due to albumen, is permanent: but disappears immediately if due to phosphates. This addition of acid after boiling should never be omitted, since the most practised eye cannot distinguish between the cloud produced by phosphates and albumen, by appear- aaice only. Cautions, {a.) The addition of the nitric acid not unfre- quently carries down some of the coagulated albumen into the unboiled layer of urine and thus causes the cloud to be less thick than before: phosphates never cause this, but the urine becomes absolutely clear as before boiling; sKght brown coloration only, occurring from the addition of the nitric acid. (&.) Should the urine be turbid from the presence of urates, it quickly becomes clear on the application of sKght heat: and as it is desu-able before testing for albumen to have a clear solution, the whole of the test tube should be passed two or three times through the flame of the lamp until the urates are dissolved: the upper stratum of the urine
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