178 ANNUAL OF SCIENTIFIC DISCOVERY. 



RIGHT AND LEFT-HANDED POLARIZATION. 



. M. de Gernez has made the interesting discovery that a super- 

 saturated solution of left-handed double tartrate of soda and am- 

 monia does not crystallize in contact with a fragment of the same 

 salt right-handed, and vice versa. From an inactive supersaturated 

 solution of double racemate of soda and ammonia, a fragment of 

 a right-handed crystal determines only the precipitation of right- 

 handed crystals ; while a portion of the same liquid in contact with 

 a left-handed crystal produces a deposit of the left-handed salt. 

 Ity this simple process either of the two constituent parts can be 

 separated at will from the double racemate of soda and ammonia. 

 Quarterly Journal of Science, 18G7. 



LUMINOSITY" OF PHOSPHORUS. 







From the experiments of Dr. Moffat, as stated at the meeting 

 of the British Association for 1867, phosphorus in a luminous state 

 produced phosphorous and phosphoric acids and ozone also; 1 it is 

 also non-luminous in a temperature below 39 F., and luminous 

 above 45 F., the temperature of luminosity and non-luminosity 

 varying with the atmospheric pressure and with the direction of 

 the wind. From a series of experiments extending over four 

 years, it appears that the equatorial or sea wind is that of phos- 

 phorescence and ozone, and that the polar or land wind is that of 

 non-luminosity and no ozone. The ocean being the reservoir of 

 ozone, he suggested the probability that this phosphorescence is 

 the chief source of its development, and that, were it not for the 

 modifying influence of the polar or trade winds, ozone at sea 

 would be a constant quantity. 



Sir William Thompson remarked, in connection with the paper, 

 that the phenomenon of luminosity stored up in ice, and produced 

 after its melting, was certainly one of the most startling in physi- 

 cal science, the luminosity having been induced by the previous 

 presence of non-luminous phosphorus at a low temperature. 



MICROSCOPICAL EXAMINATION OF COAL ASH FROM THE FLUE 



OF A FURNACE. 



When coal is burned in a furnace to which atmospheric air has 

 free access, a portion is converted into gaseous and volatile mat- 

 ter, and the incombustible substance which remains is the ash. 

 The amount of ash in coals from different localities is very vari- 

 able ; it is said to range from 1 to 35 per cent. The ash or dust, 

 which is the subject of this paper, was collected from the flue of 

 my steam-boiler furnace, in which common engine coal is used as 

 fuel. This coal leaves a considerable amount of incombustible 

 matter. The dust is of a reddish-brown color, and free from soot 

 or carbonaceous particles. When this dust is examined under the 

 microscope with a power of 40 or 50 diameters, it is found to con- 

 sist of ferruginous matter and crystallized substances, some par- 

 ticles transparent, others white and red. It contains also a num- 



