The same processes of fixation apply equally well to galvanic phantoms, that is to say, to the galvanic fields produced by the passage of a current in a conductor, and which consists of analogous lines of force.  The processes may be employed very efficaciously and with certainty of success.—­La Nature.

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A CHIPPENDALE SIDEBOARD.

[Illustration:  A CHIPPENDALE SIDEBOARD.]

Our illustration this week is of a unique and handsome piece of Chippendale work.  The outline is elegant, and the scrollings delicate.  The pedestals are peculiar in their form, the panels being carved in draperies, etc.  In the frieze are two drawers, with grotesque heads forming the handles.  The back is fitted with shaped glass and surmounted by an eagle.  The whole forms a very characteristic piece of work of the period, having been made about 1760-1770.  As our readers are aware, Thomas Chippendale published his book of designs in 1764, with the object of promoting good French design in this field of art.  This piece of furniture was sold at auction lately for 85 guineas.—­Building News.

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LIQUEFACTION OF THE ELEMENTARY GASES.

By JULES JAMIN, of the Institute of France.

The earlier experiments of MM.  Cailletet and Raoul Pictet in the liquefaction of gases, and the apparatus by means of which they performed the process, were described in the Popular Science Monthly, March and May, 1878.  The experiments have since been continued and improved upon by MM.  Cailletet and Pictet, and others, with more complete results than had been attained at the time the first reports were published, and with the elucidation of some novel properties of gases, and the disclosure of relations, previously not well understood, between the gaseous and the liquid condition.  The experiments of Faraday, in the compression of gases by the combined agency of pressure and extreme cold, left six gases which still refused to enter into the liquid state.  They were the two elements of the atmosphere (oxygen and nitrogen), nitric oxide, marsh-gas, carbonic oxide, and hydrogen.  Many new experiments were tried before the principle that governs the change from the gaseous to the liquid, or from the liquid to the gaseous form was discovered.  Aime sank manometers filled with air into the sea till the pressure upon them was equal to that of four hundred atmospheres; Berthelot, by the expansion of mercury in a thermometer tube, succeeded in exerting a pressure of seven hundred and eighty atmospheres upon oxygen.  Both series of experiments were without result.  M. Cailletet, having fruitlessly subjected air and hydrogen to a pressure of one thousand atmospheres, came to the conclusion that it was impossible to liquefy those gases at the ordinary temperature by pressure alone.  Previously it had been thought that the obstacle to condensing gases by pressure alone lay in the difficulty of obtaining sufficient pressure, or in that of finding a vessel suitable for manipulation that would be capable of resisting it.  M. Cailletet’s thought led to the discovery of another fundamental property of gases.