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are then very strongly marked, and are indicated by a diminution of tem- 
perature. 
4th, The elevation or diminution of the temperature varies only according 
to the nature of the liquids employed ; they vary equally for the same mixture 
according to the relative properties of the two liquids which compose it. 
5th. The influence of the relative proportions may even aftect the ther- 
mometric result, so as to produce in the same mixture first cold and then 
heat. Five equivalents of alcohol, mixed with one equivalent of chloroform, 
produce an elevation of temf)erature amounting to 4'5 centigrade ; whilst, 
on the contrary, a mixtme of five equivalents of chloroform with one of 
alcohol produces a diminution of temperature equal to 2‘5° centigrade. 
6th. The initial temperature of the liquids when mixed has a sensible 
effect on the result in general : the higher the initial temperature the more 
marked is the thermometric fall. 
7th. Liquids undergo a change of volume as well as of temperature when 
they are mixed. Sometimes they expand, as with alcohol and sulphide of 
carbon ; sometimes they contract, as in the case of alcohol and ether. 
8th. There is no apparent relation between the changes of tempei-ature and 
volume ; some mixtures which contract produce heat, while others which 
also contract produce cold. — Vide Comptes Rendus, October 24th, p. 673. 
The Origin of Wine Ferments. — On this question M. Bechamp has been 
delivering his opinions, which may be thus summed up : — 
1st. The presence of air is necessary neither for the development of the 
ferment, nor the commencement of the vinous fermentation. The grape 
itself brings everything necessary for the perfect accomplishment of all the 
phenomena. 
2nd. The surface of the grape may carry the sporules and mycelium of the 
ferment. 
3rd. The stalks and leaves of the vine may carry the same organisms as 
those spores, which may in fact be met with in the tissues of various plants. 
4th, Fermentation may be set up in sugar by the introduction of grape 
stalks and vine leaves, or by the petals of the red poppy. 
5th. Microscopic examination of the waxy matter on a ripe gmpe shows 
organized bodies, the same as those said to be produced in fermentation. — 
Yide Coiwptes Rendus, t. LIX., Xo. 15. 
GEOLOGY AND PALAEONTOLOGY. 
The Origin of Banded Flints has been a j)uzzle to geologists for the last 
fifty years, but we have now been enlightened upon the question by J\Ir. S. 
P. Woodward. All sorts of conjectures have heretofore been hazarded in 
explanation of the peculiar structure which banded flints present. Those 
with the furrowed surface were considered by Parkinson to be the 
petrified remains of the Anatifa, or duck-barnacle. Dr. Bowerbank, 
according to the writer’s statements, considers them fossilized sponges ; a view' 
which is objectionable, because of the fact that, when slit and polished the 
banded portions show no microscopic peculiarity to distinguish them from 
the adjacent unhanded flint, and no organic structure, save where they invade 
