Manual of qualitative analysis / by Robert Galloway.

  • Galloway, Robert.
Date:
1861
Catalogue details

Licence: Public Domain Mark

Credit: Manual of qualitative analysis / by Robert Galloway. Source: Wellcome Collection.

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    150 millimetres, and the other of 35 millimetres. The indigo solution is made by dissolving 1 part of indigo and 8 parts of fuming sulphuric acid, diluting with 1500 to 2000 parts of water, and filtering. In the following experiments the prism was moved hori- zontally before the eye, so that the rays of the flame always passed through gradually thicker layers of the medium. The alkaline substances, brought singly into the melting- space, exhibited the following changes :— 1. Chemically pure chloride of calcium produces a yellow flame, which, even with very thin layers of the indigo solu- tion, passed through a tinge of violet into the original blue lamp flame. 2. Chemically pure chloride of sodium, the same. 3. Chemically pure carbonate or chloride of potassium appears of a sky blue, then violet, and at last of an intense crimson red, even when seen through the thickest layers of solution. Admixtures of soda or lime do not hinder the reaction. 4, Chemically pure carbonate or chloride of lithium gives a carmine-red flame, which, with increasing thickness of the medium, becomes gradually feebler, and disappears before the thickest layers pass before the eye. Lime and soda are also without influence on this reaction.