434 Miscellaneous Intelligence. 
exert on crystals in ia of formation. I showed that by varying a 
pound, we may by oe means vary the molecular forces which preside 
in crystallization and cause a change in 7 crystalline type of the sub- 
stance, in case the substance is susce ptible of becoming dimorphous. 
M. Pasteur, ee of Chemistry at the Faculty of Sciences at Stras- 
burg, has obtained remarkable results of this nature, with dimorphous 
substances asion left and right (or non- porernocet>) saat 
crystals ; using the two hemihedral forms of one and the same com 
pound, as the neutral tartrate of ammonia, sa of in chafing num- 
bers of this Journal. These two forms belong to the system of the 
right rhombic prism (trimetric), and differ only in their pene hemi- 
edrism. But M. Pasteur has obtained with each of t two forms 
a second form, wholly unrelated to the first, sete aeinitlising in the 
oblique rhomboidal system [monoclinic ?], which make i in all four hemi- 
hedral forms not superposable obtained with one substance. 
To obtain this result, it is only necessary to take a solution of one 
or the other variety of this trimetric tartrate, the right or left, and add 
a small agents of cacao = of ammonia; the malate does not 
appear to enter into the compound; it exerts an action of presence 
which «st the silicon of equilibrium of the molecules . Pas- 
teur calls this new kind of hemihedrism, tetartohedrism ; and the forms, 
tetartohedral. 
Coloring matter of Flowers.—This question has been studied by sev- 
eral chemists, and still it is beyond doubt, one of the most obscure sub- 
jects in vegetable chemistry. Botanists have long admitted that flowers 
owe their color to two sre os pn: a blue, called cyanic, and 
the other yellow called xanthi or some time the blue color of blue 
flowers was attributed to the ital of saidikol ; but M. Chevreul showed 
that this oe is always reddened by acids, which fact set the indigo 
theory as 
MM. Frémy and Cloez have isolated the blue principle and they call 
it cyanine. To obtain it, they treat with boiling alcohol the petals of 
the violet or iris, until the flower is colorless and the liquid takes a fine 
blue tint. This tint disappea , but reappears on evaporating the 
This coloring matter is * unrysalinale acids turn ‘tt red, alkalies 
rreen ; it combines with lime, baryta, etc; sulphurous, phosphorous 
and other acids discolor it ; bc resumes its blue color through the pres- . 
a2 of the oxygen of the 
he coloring material of nee peonies, some dahlias, &c., is a mod- 
ifeation of cyanine ; the vegetable juices have an acid reaction (which 
ehanges the blue cyanine to red), while the juices of blue flowers are 
n the presence of alkalies, the rose color becomes first blue 
and then green. . 
