468 Intelligence and Miscellaneous Articles. 



Once the ozone is liquefied in the capillary tube, it remains in 

 that state long enough, even under the pressure of the atmosphere, 

 for it to be examined either through the liquid ethylene or the 

 refrigerated tube being withdrawn for a moment from that liquid. 

 The deep-blue liquid gradually diminishes in volume : the vapori- 

 zation of the ozone is sufficiently slow, its diffusion sufficiently rapid. 

 for the gas to appear colourless above the nearly black liquid ; it is 

 only at the moment when the last traces of the liquid disappear that 

 one ascertains the production of an azure-blue gas. The vaporiza- 

 tion of the liquid ozone would bring back the system to its initial 

 state, if the ozone were not slowly decomposed by the mercury 

 emploved to compress the gases. — Coniptes Bendiis de FAcademu 

 des Sciences. May 1, 1882, pp. 1249-1251. 



ON THE ACTION OF TELEPHONIC CURRENTS UPON THE 

 GALVANOMETER. BY M. DE CHARDONNET. 



If, iu the telegraphic circuit, the receiver be replaced by a very 

 sensitive galvanometer, and the transmitter be influenced by means 

 of a diapason, an organ-pipe, or the voice, no deflection is observed 

 as long as the sound keeps the same intensity ; but as soon as the 

 sonorosity is increased or diminished, the needle is deflected : the 

 direction of the deflection varies according to whether the ampli- 

 tude of the vibrations of the sounding body is increasing or de- 

 creasing. The effect is more marked when the transmitter is 

 shaken by a noise of short duration, such as a detonation, or by a 

 body lightly tapped upon the vibrating plate. In this last case the 

 galvanometer-needle leaps like the seconds-hand of a clock. The 

 experiment also succeeds very well when the sounding body is 

 briskly moved nearer to or away from the transmitter. These 

 deflections appear, of course, much more distinctly when a micro- 

 phone-transmitter, like Ader's, is employed ; but they are visible 

 with every kind of telephone. 



The explanation appears very simple, at least for the whole of 

 the facts collectively : — 



As long as the oscillations of the vibrating plate retain the same 

 amplitude, and consequently the same velocity, the currents induced 

 alternately in the two directions at each complete vibration com- 

 pensate each other's action upon the galvanometer, whether they 

 emanate from an electromagnet or a microphone ; but if the oscil- 

 lations tend towards zero, for example, each odd semioscillation 

 has more amplitude than the following even semioscillation, and 

 the direct and the inverse induced currents no longer put in motion 

 the same quantities of electricity. The residues, of the same sign 

 at each complete oscillation, accumulate so as to deflect the needle : 

 and the more rapidly the sound diminishes, the greater is the de- 

 flection. This is what experiment demonstrates. — Comptcs Rendu* 

 dr. F Academic des Sciences, March 27. 1 V S2. t. xciv. p. 857. 



