An outline for the quantitative analysis of urine / by Henry Erni.

  • Erni, Henry
Date:
1860
Catalogue details

Licence: Public Domain Mark

Credit: An outline for the quantitative analysis of urine / by Henry Erni. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    weight has previously been determined. Into the nearly dry mass we stir, by means of a platinum wire, a known weight (one to two grms.) of finely ground platinum sponge. We evaporate to full dryness, and after bringing the capsule for some time into the air- bath, we weigh. Deducting from the gross weight that of the crucible and platinum sponge, we find the whole amount of solids. To learn the quantity of fixed salts, we ignite the mass over a spirit- lamp, until all the carbon is burnt off—an operation greatly pro- moted by the porous platinum sponge. Deducting now from the gross weight obtained, that of the capsule and platinum, we obtain the amount of fixed salts—ashes. If a more minute analysis becomes desirable, we can from this mass easily separate, 1st, The amount of salts soluble in water, (potassa and soda, uni- ted with sulphuric, chlorohydric, and phosphoric acids,) from, 2dly, Those soluble in chlorohydric acid, such as lime and mag- nesia, combined with phosphoric acid. We treat the mass first with boiling water, and after that extract with the above acid.* The platinum sponge remains behind after extracting the ashes with both fluids, and may again and again be made use of. From a trace of silicic acid found in urine, it is freed by potassa. For information in regard to the quantitative determination of each single inorganic constituent, we refer to the works of Eose and Fresenius. The solid matter varies in quantity much less in urine discharged within twenty-four hours, than the watery contents. Hence, the variable density of urine must be attributed to the latter. For in- stance, the same amount of solids may at one time be dissolved in 900 grms. of water; at another, in 1300 grms. The causes which much contribute to the augmentation of water, are various drinks, polydipsie, mental anxiety, hysteric affections, diabetes. Those which diminish it, are fever, heart-disease, abundant sweats, agony. This diminution may vary between 700 and 250 grammes—Bee- querel. From a large number of observations, Becquerel gives the [phy- siological] average amount of solids in the urine of twenty-four hours; for a man 39 grms, for a woman 34 grms. According to Bird, the excretion of solids by the kidneys, in the adults, within the same time, oscillates between 40 and 45 grms. [350 to 700 grains.] The causes which affect the diminution Oi solid matter * Pharmaceut. Centralb, 1850. p. 534.
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