CHEMICAL SCIENCE. 183 



acid method, the cubic meter of oxygen having cost in this case not 

 more than one or two francs ; and in practice the price would prob- 

 ably be much less than this, since the sulphurous acid might readily 

 be utilized. 



It is worthy of remark that the oxygen prepared from sulphuric 

 acid can be easily obtained in a state of chemical purity ; that made 

 from black oxide of manganese is always contaminated with nitrogen. 

 Ann. de Chim. et Phys. 



PROPERTIES OF LIQUID CARBONIC ACID. 



In a recent communication to the Royal Society, Mr. Gore, the 

 well-known physicist, showed how a small quantity of liquid carbonic 

 acid might be readily and safely prepared in glass tubes, closed by 

 stoppers of gutta percha, and be brought in a pure state into contact 

 with any solid substance, upon which it may be desired to ascertain 

 its chemical or solvent action, or be submitted to the action of elec- 

 tricity, by means of wires introduced through the stoppers. 



By immersing about fifty substances in the liquid acid, for various 

 periods of time, he has found that it is comparatively a chemically 

 inert substance, and not deoxidized by any ordinary deoxidizing agent, 

 except the alkali metals. Its solvent power is extremely limited. It 

 dissolves camphor freely, iodine sparingly, and a few other bodies in 

 small quantities. It does not dissolve oxygen salts, and it does not 

 redden solid extract of litmus. It penetrates gutta percha, dissolves 

 out the dark brown coloring matter, and leaves the gutta percha 

 undissolved, and much more white. It also acts in a singular and 

 somewhat similar manner upon India rubber. The India rubber, 

 while in the liquid acid, exhibits no change ; but immediately on being 

 taken out, it swells to at least six or eight times its original dimen- 

 sions, and then slowly contracts to its original volume, evidently from 

 expansion and liberation of absorbed carbonic acid, and it is found to 

 be perfectly white throughout its substance. These effects upon gutta 

 percha and India rubber may prove useful for practical purposes. 



The liquid acid is a strong insulator of electricity.; sparks (from a 

 RuhmkorfPs coil) which would pass readily through -g%ds inch of cold 

 air would with difficulty pass through about y^th of an inch of the 

 liquid acid. 



In its general properties it is somewhat analogous to bisulphide of 

 carbon, but it possesses much less solvent power over fatty substances. 



OZONE, NITROUS ACID, AND NITROGEN. 



The following communication has been made to Silliman's Journal 

 by T. Sterry Hunt, F.R.S: The formation of a nitrite when moist 

 air is ozonized by means of the electric spark (the old experiment of 

 Cavendish), or by phosphorus, was shown by Rivier and de Fellen- 

 berg, who concluded that the reactions ascribed by Schonbein to 

 ozone were due to traces of nitrous acid. The subsequent experi- 

 ments of Marignac and Andrews have, however, established that 

 ozone is really a modification of oxygen, which Houzeau has shown 

 to be identical with the so-called nascent oxygen, which is evolved, 



