A treatise on poisons, in relation to medical jurisprudence, physiology, and the practice of physic / By Robert Christison.

  • Christison, Robert, Sir, 1797-1882.
Date:
1836
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on poisons, in relation to medical jurisprudence, physiology, and the practice of physic / By Robert Christison. Source: Wellcome Collection.

    914/918 (page 876)
    DESCRIPTION OF THE PLATE. 1. Small funnel-shaped tube for testing minute portions of liquids. 2. Apparatus for the distillation of fluids suspected to contain acids, one- seventh the natural size. 3. Tube for reducing very small portions of arsenic or mercury. The figure is of the natural size. The ball may be blown larger, if the material to be reduced is bulky. 4. A small glass funnel for introducing the material into the tube Fig. 1, without soiling its inside. 5. The ordinary apparatus for disengaging sulphuretted-hydrogen. The funnel must be a little longer than the emerging tube. The fluid should not be at any time much higher than in the figure, in order to secure the operator against its effervescing up into the emerging tube. The figure is a third of the natural size. 6. Instrument for washing down scanty precipitates on filters. It is a thin bottle capable of standing the fire—half-filled with water, which may be boiled on occasion,—and having its cork pierced with a small tube drawn at its outer end to a very fine bore. The breath is impelled into the bottle, and, the bottle being then reversed, a very fine stream issues with great force. This exceedingly useful and simple appara- tus is the invention, I believe, of Berzelius. 7. Tubes of natural size for collecting small portions of mercury by the process, p. 343. 8. Pipette, one-third the natural size, for removing by suction fluids lying over precipitates. Some have a rectangular bend in the upper part, by means of which the operator sees better the point of the instru- ment when in action; but such pipettes are very difficult to clean. That represented in the figure is easily cleaned with a feather. 9. Apparatus for reducing the sulphurets of some metals by a stream of hy- drogen. A, the vessel with zinc and diluted sulphuric acid, the lat- ter of which may be renewed by the funnel B. C, a ball on the emerging tube to prevent the liquid thrown up by the effervescence from passing forward. D, E, corks by which C and G are fitted into F, the tube which contains the sulphuret at F. G, the exit-tube for the sulphuretted-hydrogen, plying into a vessel containing acetate of lead. When the hydrogen has passed long enough to expel all the air, the spirit-lamp flame is applied at F.; and when sulphuretted- hydrogen is formed, the lead solution is blackened. The figure is one- third the size of the apparatus. EDINBURGH : PRINTED BY JOHN STARK, Old Assembly Close.