[Illustration]

In using the apparatus the sulphur is first kindled by introducing a red hot wire through the tube, B, and replacing the stopper that has been momentarily removed for the introduction of the same.  A slight blast is now maintained from the bellows that are in connection with the pipe, D, until the whole of the sulphur is thoroughly kindled, when a somewhat more powerful blast may be applied.  When the apparatus above described is in full working order, from 2 to 3 lb. of sodium carbonate may be converted into sodium sulphite in less than half an hour, or several gallons of water saturated.  I have also on connecting the apparatus with a powerful refrigerator obtained in a short time a large quantity of liquid SO2.  It will be found advantageous, however, during the preparation of sulphurous anhydride, to employ a layer of water covering the bottom of the vessel to about 1 inch in depth.  Carbonic anhydride and phosphoric anhydride may also be readily obtained in any desired quantity by slight alteration; but in case of phosphorus the air must be allowed to enter only gently, since a rapid current would at all times determine the fracture of the vessel.—­Chem.  News.

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THE ARRANGEMENT OF ATOMS IN SPACE IN ORGANIC MOLECULES.[1]

[Footnote 1:  Ueber die raumliche Anordnung der Atome in organischen Molekulen, and ihre Bestimmung in geometrisch-isomeren ungesattigten Verbindungen.  Von Johannes Wislicenus.—­Abhandlungen der mathemalisch-physischen Klasse der Konigl.  Sachsischen Gesellschaft der Wissenechaften.  Band XIV., No. 1.]

The expression “chemical structure,” as commonly used by chemists, has, as is well known, nothing to do with the arrangement of atoms in space.  The structural formula does not profess to represent spatial relations, but simply the connections which, after a careful study of the transformations and modes of formation of the compound represented, are believed to exist between the atoms.  Nevertheless, although we do not commonly consider the question of space relations, it is clear that atoms must have some definite positions in space in the molecules, and the only reason why we do not represent these positions is because we know practically nothing about them.  The most definite suggestion concerning space relations of atoms which has been made is that of Le Bel and Van’t Hoff.  The well known hypothesis of these authors was put forward to account for a certain kind of so-called physical isomerism which shows itself in the action of substances upon polarized light.  Since this hypothesis was proposed, the number of cases of “abnormal isomerism,” that is to say, of cases of isomerism which cannot be accounted for by the commonly accepted method of explaining structure, has increased to a considerable extent, and the necessity for some new hypothesis, or for some modification of the old ones, has come to be pretty generally recognized.  Among the cases of isomerism which it is at least difficult to explain by the aid of the prevailing views are those of maleic and fumaric acids; citraconic and mesaconic acids; certain halogen derivatives of crotonic acid and of cinnamic acid; and coumaric and coumarinic acids.