‘ 
486 Screntific Intelligence. 
grows darker, but still remains of a not pronounced gray tint. 
he water was taken from various localities—from the conduits 
near the city of Geneva—from the Arve. Distilled water was 
and orange were perhaps too much enfeebled, either by the great 
length of water traversed by the light or by the employment of 
a too feeble source of light. Through four meters and even eight 
meters of water the author could not detect the band between 
E and 6 which Vogel found in the light in the grotto of Capri. . 
This appears to indicate that this band is due to substances In 
solution in the water.— Comptes Rendus, March 10, 1884, pp- 
624-626. 
duced at the temperature 0 at a point where the magnetic intens- 
ity is 1 and @ is a constant. Fo i i 
silver it varies from 0-008 to 0:009. This deviation can be con- 
sidered as due to a heterotrophy which the metal assumes in the 
magnetic field and is analogous to that which light undergoes In 
falling normally upon a doubly refracting substance. he- 
. 
ep 
nomenon is very feeble in an alloy of bismuth and lead of equal 
weight which is very malleable. It is zero in lead according to 
Dr. Hall. The crystalline state of bismuth appears therefore to 
