Prussian Blue and Starch.—Starch Sugar.—Red Snow. 69 
PRUSSIAN BLUE AND STARCH. 
M. Vincent, a French apothecary, states* that if four parts of: 
starch and one part of Prussian blue be well triturated together 
in a mortar, and then boiled in a large quantity of water, the 
liquor acquires a green colour before it begins to boil; when it 
becomes brown, and a precipitate is formed, which, though treated 
with acids, does not resume its blue colour. The liquid forms a 
fine Prussian blue when a solution of sulphate of iron mixed with 
an equal volume of solution of chlorine is added to it. When 
evaporated no gluey substance is deposited; but, if evaporated 
to a small volume, on being suffered to cool, it yields a glutinous 
matter, which dries in the open air, and may again be easily dis- 
solved in water. The starch, therefore, has changed its nature 
and been converted into a kind of gum. 
STARCH-SUGAR. 
The process of M. Kirchoff for converting the amylaceous fe- 
cula (starch) into sugar by means of sulphuric aeid, has already 
received some uséful applications ; but the most useful is, doubt- 
less, the conversion of this sugar into beer. Mingled in a proper 
quantity of water, set in fermentation and hopp’d according to 
the method of brewers, this syrup furnishes a beer which is light, 
brisk, strong, and of an agreeable savour. This refreshing and 
healthy beverage may be prepared any where; it requires neither 
mill nor expensive vessels, so that the cultivator and artisan may 
make it in their dwellings. Already two manufacturers are em- 
ployed in preparing it in quantities, and they estimate that it 
will only cost them a centime the livre. (jd. the gallon.) 
RED SNOW. 
Our readers must all have heard of the red snow stated to have 
been found by our northern navigators lying upon the surface of 
snow lodged in ravines, for upwards cf 100 miles along the coast 
of Baffin’s Bay. Quantities were collected and brought home in 
bottles ; that is, the colouring substance and the water of the snow 
on which it lay, with other substances apparently foreign, which 
had been taken up with the snow. ‘Dr.Thomson has published the 
result of experiments made upon small quantities of the colouring 
substance. On opening a phial of what had been collected, an 
offensive smell, similar to that of putrid sea weed, or excrement, 
was perceptible. After some time the colouring matter subsided, 
leaving the water colourless. Examined with a magnifier it ap- 
peared to consist of minute particles, somewhat globular, of a 
brownish-red colour. This, separated on a filter and dried, 
*" In the Journ. de Pharm. for June 1818. 
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