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Scientific Intelligence, 
considered electrical, but upon what grounds I know not. In 
my own experiments, I never could discover any electrical exhi- 
bitions when sugar was insulated and broken, or suffered fric- 
tion in contact with the gold-leaf electroscope and its condenser. 
It is not generally known, that if we simply break a piece of 
of loaf-sugar, or even sugar-candy, between the fingers in the 
dark, a flash of light appears. I find that the same phenome- 
non takes place with beet-root sugar as with that from the cane ; 
and by continued friction of the fragments upon each other, a 
continuous light is kept up. This occurs also when the sugar 
is rubbed on alum, rosin, &c. or triturated in a mortar. When 
sugar is broken, or suffers friction in water^ alcohol^ or etJier^ 
light is in like manner manifested, as is the case also in carbonic 
acid, oxygen and chlorine, A bit of sugar was allowed to re- 
main in nitrous oxide, and another fragment in chlorine. Both 
emitted light when broken ; and in the latter it seemed more in- 
tense, and of an orange tinge.” 
49. On the Luminosity of the Ashes of Wood steeped in solu- 
tions (fi Lime, ^c, — The following observations on this subject 
are communicated by Mr John Murray. In Yol. III. p. 343. 
of the Edinburgh Philosophical Journal, Dr Brewster has de- 
tailed some singular instances of luminosity developed by wood, 
&c. when previously steeped in solutions of lime and magnesia. 
I have long observed similar phenomena, such as the increased 
light which takes place when shreds of paper, bits of straw, &c. 
are burned to iMte ash, or amianthus, talc, (when calcined), &c. 
and introduced into the outer margin of the flame of a candle. 
You may remember that Sir H. Davy had already pointed out 
that incombustible matters, as asbestus, &c. increased the light 
of flame, and he even suggested that it might be practically use- 
ful in this way ; and though he has not attempted to solve the 
phenomenon, I do not think it a problem of much difficulty. 
In reference to the intense luminous star which appears between 
charcoal points in a powerful galvanic apparatus, when the cir- 
cuit is formed, the charcoal is always primarily reduced to the 
white state noticed by Dr Brewster. The very brilliant light, 
too, exhibited by bringing magnesia and some of the other 
earths in contact with the flame of the condensed gases in the 
oxy-hydrogen blowpipe, seems explicable on the same principle. 
