Observations on the healthy and diseased properties of the blood / by William Stevens.

Date:
1832
Catalogue details

Licence: Public Domain Mark

Credit: Observations on the healthy and diseased properties of the blood / by William Stevens. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    At the moment tliat this water is first taken from* the spring it is supersaturated with free carbonic acid; but, notwithstanding this excess of both acid and carbonates, when the water is just taken from the fountain, it does not redden the litmus, neither does it give a brown colour to the turmeric paper * yet when this water has been exposed for a short time to the air, the acid is soon removed, and when this is effected, the water then gives a decided broAvu colour to the alkaline test; but not until the greater part of the free acid has l)een removed by exposure for a short time to the atmospheric air, or when the acid is expelled more suddenly by a gentle heat. If there be no carbonic acid in the blood, and if the serum owed its ])roperty of changing the colour of the test to a free alkali, it ought then to possess this power in as great a degree when it first separates as it does after it has been exposed for some time to the atmosphere. But this is not the case; for healthy serum, when it first separates, seldom changes the colour of turmeric paffer. It is only after exposure to the air, and after the removal of the carbonic acid, that the carbonates in the serum then give a decided brown colour to the turmeric paper. Litmus paper reddened with an acid is a more delicate test, either for the free alkalies or the alka- line carbonates, than turmeric, and on this, when it fiist sepal ates, the serum generally produces a slight alkaline ie-action; but this quality is at first so faint, that I have scarcely met with a’n instance where the